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By Keir Murray
1503: Ladies and gents, I'll sign off here now. Thanks very much for joining me this afternoon. It has been an astonishing title race. Look out for the highlights late this evening and I hope you can join us next Saturday when Celtic and Motherwell contest the Scottish Cup final. All the best.
1501: "I am surrounded by a good group of guys who pushed me and challenged me to get back to my best." Rangers midfielder Maurice Edu thanks his team-mates from helping him through a sticky patch earlier in the season.
1459: Our text system is going in to meltdown. Here's an anonymous one to 80295: "Congratulations Walter Smith, I for one doubted bringing you back, I remember 9 in a row and thought we would remember what you did. Now, with no money, club in dire banking trouble, thank you for even more brilliant memories, and proving me wrong. Walter For a Knighthood."
1456: "It's the best feeling of my life. It's a present for Walter. He is a great man. I would like to say thank you to him," says Rangers left-back Sasa Papac.
1454: Every Rangers player is taking a turn to hold the trophy to the Rangers fans. It really is party time for the club's supporters.
1452: "I just love the club. I love it. I have two years left here and I want to extend that. You cannot beat moments like this. It's incredible." Rangers goalkeeper Allan McGregor makes it plain that he wants to stay at the club
1448: We will have all sorts of text and video features to follow here on the BBC Sport website. Tune in to Sportscene on BBC Two Scotland at 2200 BST, if you prefer TV coverage, or log on to the site at around 2300 BST for online highlights of today's match action.
1445: Well, there will be many "what ifs?" to be chewed over by the Celtic fans, and "what nows?" for both Rangers and Celtic supporters. Celtic's 3-2 defeat by Inverness was the turning point in recent weeks. That will haunt Celtic fans over the summer.
1444: "We've got a great bunch of lads who have worked extremely hard for us. They've been brilliant. I'm just delighted the team has managed to win - that's the main thing. It's always the main thing. I just feel it's the right time for me to leave and it's the right thing for Rangers." Rangers' departing manager Walter Smith
1442: "We are the champions" is sung by the travelling fans. As my colleague Andy points out - no set of fans has ever mastered the singing of that number. Key and timing are crucial, I reckon.
1441: Rangers captain David Weir holds aloft the SPL trophy and Rugby Park erupts!
1440: Rangers' chief executive Martin Bain and Ally McCoist are embracing - I guess that's a bear hug. Sorry...
1439: SPL chief executive Neil Doncaster presents the Rangers squad with their league winners' medals as "Penny Arcade" is blasted over the PA system
1438: "This is not the end, it's just the beginning," says a defiant Celtic manager Neil Lennon, to roars of approval from a packed stadium.
1436: David Weir leads the Rangers players out the tunnel to lift the trophy. New owner Craig Whyte, scarf draped round his shoulders, looks on approvingly.
1435: But at Kilmarnock, the trophy is being carried towards the podium in the centre-circle. It's almost that time...
1434: Celtic manager Neil Lennon is addressing the packed stadium at Parkhead. The fans are loving it.
1432: With those three goals for Rangers in the opening seven minutes, Helicopter Sunday did not quite have the same drama as the final day of the 2004/05 season, but it was thrilling all the same.
1431: And now the podium is being built on the Killie pitch for Rangers to lift the silverware.
1430: More accurately, it is being carried through the front door of Rugby Park - it cannot walk.
1429: The SPL trophy is coming through the front door of Rugby Park.
1427: Rangers captain David Weir tells BBC Radio Scotland listeners that he still hasn't made up his mind about whether to continue playing. But he is certain of something: that Walter Smith's departure is a loss to the club.
1426: Congratulations to Rangers and commiserations to Celtic - they have given their fans bags of excitement in a tense SPL title race.
1423: Although the Celtic fans are hurting, they give the team and manager tremendous backing as they walk round Celtic Park despondently. Meanwhile, down the M77, Rangers' manager-in-waiting Ally McCoist says of Walter Smith: "What a service that man his given this football club."
FULL-TIME: Dundee United 2-1 Hearts
1422: Asked if this is his greatest triumph, Walter Smith says he cannot pick and choose. He tells BBC Scotland reporter Chick Young the time is right to leave.
FULL-TIME: Celtic 4-0 Motherwell
1419: Rangers manager Walter Smith comes on to the pitch to greet his players. What an achievement - 10 league titles in two spells in charge of the Ibrox side. It's title number 54 for Rangers.
FULL-TIME: Kilmarnock 1-5 Rangers Rangers are champions
1417: Rangers' hat-trick hero Kyle Lafferty makes way for David Healy and Madjid Bougherra is back on.
1415: The big Algerian is not a happy chappy as he hobbles off. Looking at re-runs of the tackle, Fisher could have been sent off for that challenge. David Healy looks like he will come on in Bougherra's place.
1414: Gary Fisher slides in to the left shin of Madjid Bougherra and is booked for a reckless challenge. That was a sore one.
1411: What sort of damage will Celtic's emphatic win have on Motherwell when they face them again in the Scottish Cup final? Still 4-0 to Celtic in that one.
1410: Nikica Jelavic is cheered by the Rangers fans as he is substituted for El Hadji Diouf. The Croatian striker is given proper man-hugs by Walter Smith and Ally McCoist.
1408: Lee McCulloch tries to get his name on the scoresheet but is horribly off-balance. The experienced midfielder looks embarrassed.
1407: Killie's James Fowler takes exception to Madjid Bougherra's showboating and sends the Algerian crashing to the turf.
1405: Former Killie player Steven Naismith smacks a shot off the crossbar as Rangers come close to hitting the hosts for six.
1404: The helicopter has taken off - trophy aboard - and is heading south to Kilmarnock.
1404: Dundee United look to be finishing the season with a win. Sean Dillon fires in a cross that is pounced on by Jon Daly, who blasts the ball into the bottom left corner.
GOAL! Dundee United 2-1 Hearts (Daly)
1401: A cross from the right-hand side from Shaun Maloney finds Georgios Samaras. He is tackled but the ball drops to Paddy McCourt who smashes a finish beyond Lee Hollis.
GOAL! Celtic 4-0 Motherwell (McCourt)
1359: Lee McCulloch comes on for Rangers' left-sided midfielder Gregg Wylde.
1359: Auchie01 Mike Auchincloss on Twitter #bbcsportsound: "Still holding out hope! Come on Killie, only 4 more!"
1357: It looks like Lee McCulloch is going to make a late appearance for Rangers.
1356: And the Ayrshiremen go close to another goal as Garry Hay brings out a save by Allan McGregor. Just over 20 minutes to go.
1355: Rangers goalie Allan McGregor is left rooted to the spot as James Dayton's 25-yard free-kick is deflected into the net. Killie's pride is partly restored.
GOAL! Kilmarnock 1-5 Rangers (Dayton)
1352: Rangers captain David Weir volleys the ball at goal from 10 yards but his shot is saved.
1351: After his heroics this afternoon, Rangers' Kyle Lafferty misses a sitter, taking a fresh-air swipe at the ball with the goal at his mercy.
1349: Highlights of yesterday's SPL matches will be on the BBC Sport site at 1800 BST, while if you want to see the best bits from today's decisive games, then they will be online around 2300 BST. Or, of course, you can watch top quality coverage on Sportscene on BBC Two Scotland at 2200 BST.
llerrad69 on Twitter using #bbcsportsound: "Killie aren't rolling over, they are just mince. It's all gone pear-shaped since Mixu and Sammon left."
1347: "I fear for Kilmarnock now. There could be more goals. It could be six or seven. This is a containing job now." BBC Radio Scotland pundit Billy Dodds
1346: "It's great that they are having a celebration at Celtic Park after the great season that they have had - but there is definitely a helicopter heading to Kilmarnock." BBC Radio Scotland football pundit Gordon Smith
1345: Celtic Park is bouncing as 60,000 fans do a defiant huddle, applauded by manager Neil Lennon.
1344: Shaun Maloney drives at the Claret and Amber defence, shapes to shoot but drops the shoulder to leave two defenders bamboozled. And he calmly despatches a left-foot finish by Lee Hollis - class.
GOAL! Celtic 3-0 Motherwell (Maloney)
1342: It's another goal for Kyle Lafferty as the big striker secures his hat-trick, stretching to poke the ball into the Killie goal from 10 yards.
GOAL! Kilmarnock 0-5 Rangers (Lafferty)
1340: Dundee United re-start the match in a lively fashion as David Goodwillie lays off to Mihael Kovacevic who forces a terrific save from Hearts keeper Marian Kello.
jackoherts JD on Twitter #bbcsportsound: "As expected - spirited first 15 secs performance from Killie - nobody could accuse them of rolling over for Rangers."
1338: Rangers striker Nikica Jelavic curls a sweet free-kick past Cammy Bell to put the title destination beyond doubt. he wheechs off his jersey, though, and is booked by referee Craig Thomson.
GOAL! Kilmarnock 0-4 Rangers (Jelavic)
1335: In remarkably similar scenarios, Shaun Maloney and Kyle Lafferty shoot wide of the target for Celtic and Rangers respectively when they ought to have scored.
1334: Motherwell are about to kick off the second half at Celtic Park. Celtic midfielder Shaun Maloney is on for Emilio Izaguirre.
1333: Neither Killie or Rangers has made any changes. Killie caretaker boss Kenny Shiels will surely be demanding a major effort to get back into this game - he needs it to help his chances of getting the job on a more permanent basis.
1332: The teams are back out at Rugby Park.
1329: OK, what could happen in the final 45 minutes of the league season? If you are just logging on, as it stands Rangers are on course to win the title. If Killie can pull back three goals (count 'em) to level matters at Rugby Park, and Celtic retain or build on their 2-0 lead over Motherwell, then the celebrations will be at Celtic Park. An unlikely scenario, given Rangers' recent defensive record, but if they switch off, Killie might sneak one back. And if they get one, they might get two...
1326: From DrAJ71 on Twitter using #bbcsportsound: "The fat lady has most definitely sung the bouncy."
1325: An anonymous (boo!) text to 80295: "I am a Killie fan, we've been shocking first half, but before Celtic fans all start having a go at a pathetic Killie team, don't blame us that you lost the league. Inverness? Only yourself to blame - it's football, not favours."
1322: BBC Radio Scotland's Rob Maclean, reporting from Celtic Park, tells listeners that the fans at Parkhead are making it clear to Neil Lennon that he has their support.
1320: What a 45 minutes. Or more accurately, what a seven minutes, as that was how long it took for Rangers to virtually secure their 54th title with those three goals at Kilmarnock.
Kilmarnock 0-3 Rangers Celtic 2-0 Motherwell Dundee United 1-1 Hearts
1318: Killie have come to life at the end of the first half. Allan McGregor makes another fine save to deny a fabulous strike from distance for Craig Bryson.
1317: From dthorpew on Twitter using #bbcsportsound: "Oh Samaras can score? Shame he couldn't score a penalty and not leave us relying on a pathetic Kilmarnock team."
1316: Kilmarnock midfielder Mehdi Taouil hits a free-kick through a fragile Rangers wall and into the arms of Allan McGregor. The Scotland keeper is not impressed with his defence.
1315: From Iain in Bonnyrigg by text on 80295: "No wonder people are worried about the state of Scottish football when you see the performances of teams against the Old Firm in the top six. Killie's performance is typical of the beatings handed out. The gap between the Old Firm and the rest has never been bigger."
1314: It's the turn of United's Craig Conway to blast a long-range effort narrowly over the bar. It's a decent game at Tannadice.
1313: Rangers midfielder Steven Davis smacks Cammy Bell's left-hand post with a curling shot from 12 yards.
1312: Georgios Samaras plays the ball out wide to Charlie Mulgrew and continues his run into the box where Mulgrew finds him with a return pass. The big Greek side-foots home from eight yards.
GOAL! Celtic 2-0 Motherwell (Samaras)
1309: Hearts forward David Templeton hoofs a 30-yarder at goal but keeper Dusan Pernis is equal to it and touches it over the bar. A real quality strike.
1307: How many Old Firm fans were wondering who in the Kilmarnock team could be the equivalent of Motherwell's Scott McDonald when he scored two late goals to sink Celtic on the final day when Rangers lifted the title in 2005? Craig Brysoon? Mehdi Taouil? James Dayton? Hmm - Killie don't look to have enough of a goal threat. But you just never know...
1306: Allan McGregor dives to his right to make an impressive save from a cracking shot from outside the box by Killie's James Dayton.
1305: Celtic midfielder James Forrest is booked for diving.
1305: A free-kick from David Templeton is met by a good low head flick from Gary Glen across and into the Dundee United goal.
GOAL! Dundee United 1-1 Hearts (Glen)
1303: Rangers have conceded one goal in their last nine games, BBC Radio Scotland commentator Liam McLeod reminds listeners. But what effect would a Killie goal have now, I wonder?
1301: Well, Celtic are doing their part! Gary Hooper turns in the box and his first effort is blocked. However, he is first to react to the rebound and stabs a finish past Lee Hollis, who manages to get a hand to it but is unable to keep it out.
GOAL! Celtic 1-0 Motherwell (Hooper)
1259: And Well's Shaun Hutchison flirts with his own goal for the second time in three minutes, diverting a Georgios Samaras cross just over his own bar.
1258: Motherwell's Shaun Hutchison is inches away from heading a Ki Sung-Yeung corner into his own net. Celtic are still pushing to make the breakthrough.
1257: Rangers go close to number four. Steven Davis, in top form, races through the Killie half, plays the ball out to Steven Whittaker over-lapping on the right and he sends a cross in for Steven Naismith who glances the ball a yard wide of goal.
1256: Gary Hooper plays one-two with Georgios Samaras, cuts inside Gavin Gunning but Lee Hollis races out, stays big and makes the block. Scott Brown fires the rebound wide.
1255: The opening goal at Tannadice comes out of nowhere as David Goodwillie latches on to a cross and hits a right-footed ball into the net past Hearts keeper Marian Kello.
GOAL! Dundee United 1-0 Hearts (Goodwillie)
1253: Andy Driver looks to have tweaked his groin and comes off the Tannadice pitch early. The Hearts midfielder was due for an operation in the close season for his condition.
1252: And in the east end of Glasgow, Motherwell's Shaun Hutchison heads a Tom Hateley corner over from just five yards out.
1251: Charlie Mann, that intrepid BBC Scotland reporter, says Celtic Park is rocking to the sound of "There's only one Neil Lennon".
1250: I know I mentioned the changes to the respective United and Hearts line-ups at 1229, but apologies for the late arrival of the full team lists.
1249: DUNDEE UNITED TEAM: Pernis, Dillon, Severin, Daly, Kovacevic, Conway, Gomis, Buaben, Dixon, Goodwillie, Russell. Subs: Banks, David Robertson, Douglas, Kenneth, Shala, van der Meulen, Armstrong.
1248: From Redmac by text on 80295: "Helicopter Sunday? I think Kilmarnock's keeper is having a ride in it already!"
1247: David Goodwillie spins in the Hearts penalty area and hits a shot on target that requires a superb save from Marian Kello. Still goalless at Tannadice.
1245: Motherwell goalkeeper Lee Hollis makes two good saves, first from Georgios Samaras and then from Gary Hooper. It's a good start to his debut but frustrating for Celtic.
1244: "It dies. It's dead." BBC Scotland football pundit Charlie Mann describes, with great economy, the atmosphere at Celtic Park when Kyle Lafferty scored Rangers' third goal.
1242:Eggert Jonson hits the ball sweetly but straight at Dundee United goalkeeper Dusan Pernis. Hearts have made a healthy start to the game at Tannadice.
1241: Rugby Park is swirling with noise. Killie are all at sea. They look shell-shocked.
1239: Kilmarnock have imploded. Rangers have exploded. In an utterly unbelievable start to the match, Kyle Lafferty scores his second goal, knocking the ball into the net after good work by Nikica Jelavic.
GOAL! Kilmarnock 0-3 Rangers (Lafferty)
1237: Steven Naismith starts and finishes a move for Rangers, passing to his left in midfield then advancing to the edge of the box to get on the end of Gregg Wylde's cross. He took one touch and pinged it into the corner of the net.
GOAL! Kilmarnock 0-2 Rangers (Naismith)
1235: Just before Lafferty had hit the net at Rugby Park, Motherwell's Steve Jones had a good chance at Celtic Park in the first minute but and fired just wide.
1233: It's an incredible start for Rangers, all in black today. Kyle Lafferty gets on the end of a pass from midfield and dinks the ball over keeper Cammy Bell from the edge of the box. A tremendous finish.
GOAL! Kilmarnock 0-1 Rangers (Lafferty)
1232: We're under way in the big two games.
NYAdvice on Twitter using #bbcsportsound: "Wise words. Expecting a good game from you as well, Keir. Just spent morning here in Kentucky painting the bluegrass green." Thank you - noted.
1229: OK, kick-off time is almost upon us!
1229: Hearts make six changes from the team that was defeated 3-0 by Celtic in midweek. David Obua misses out through suspension following his dismissal against the Hoops, while Marius Zaliukas, Ian Black, Ryan Stevenson, Rudi Skacel and Stephen Elliott are also left out of the squad. In their place come Darren Barr, Ruben Palazuelos, Andy Driver, David Templeton, Gary Glen and Scott Robinson to give the visitors a youthful look.
1228: Dundee United give starts to Craig Conway, Prince Buaben and Morgaro Gomis who are all set to leave in the summer. Captain Jon Daly and defenders Mihael Kovacevic and Sean Dillon are both handed starts at the expense of David Robertson, Scott Robertson and Garry Kenneth, while defender Keith Watson is also absent after having a hernia operation on Thursday.
1226: Vladimir Weiss, who seemed to enjoy his loan spell at Rangers, is posing in his club blazer for photos with the visiting fans at Rugby Park.
1224: I should mention that there are three SPL games kicking off in just five minutes' time. Dundee United and Hearts are playing at Tannadice - fourth v third.
1223: Whatever happens this afternoon, both Celtic and Rangers deserve credit for providing a tremendously exciting title race, one that has had more twists and turns than a broken Slinky.
1222: "In the last few games we have looked solid defensively and we have looked like we would score goals." Rangers assistant boss Ally McCoist
1220: Rangers assistant manager Ally McCoist admits to nervousness ahead of kick-off - but he thinks that's a healthy state to be in.
1217: BBC Scotland football pundit Chick Young informs listeners that the attendance at Rugby Park is the biggest since Elton John was tinkling the ivories at the stadium in June 2005. Hmm. Celtic fans will hope to be singing "I Guess That's Why They Call It The Blues".
1215: This, in football-speak, is "squeaky bum time", when a moistness permeates parts one would rather remained bone dry. Fans - stay calm, stay cool.
1205: Celtic have made one change from the team that played Hearts. Kris Commons is suspended after his red card at Tynecastle so James Forrest comes in to Neil Lennon's starting line-up.
1203: Vladimir Weiss, James Beattie, Kyle Bartley, who played for Rangers earlier in the season, are at Rugby Park to take in the match.
1201: We are hearing that Rangers are unchanged for the fifth match in succession.
1200: Welcome to what promises to be an incredibly tense afternoon of Scottish football. Leaders Rangers need a win at Kilmarnock to guarantee them their third consecutive Scottish Premier League title. Celtic, meanwhile, just a point behind Rangers, need to better their rival's result when they host Motherwell. If Rangers lose and Celtic draw, Celtic will win the league on goal difference.
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