All the action from Monza.
All times BST.
1 R Barrichello (Ferr)
2 M Schumacher (Ferrari)
3 J Button (BAR)
4 T Sato (BAR)
5 JP Montoya (Williams)
6 Coulthard (McLaren)
7 A Pizzonia (Williams)
8 G Fisichella (Sauber)
Lap 53 The Ferrari fans line the home straight as Barrichello leads home another one-two with seven-time world champion Schumacher. It is the first Grand Prix win for the Brazilian of the season and Button comes home in third.
Lap 52 If Button and Sato are able to hold their places BAR will move up to second ahead of Renault in the constructors' race. Meanwhile, out on the circuit Pizzonia and Coulthard tangle but the Scot stays ahead of him.
Lap 51 Britain's Button continues to chase down the Ferraris in third spot but he is 9.2 seconds off the pace as the places continue to hold steady.
Lap 50 Barrichello and Schumacher are heading for their eight one-two finish of the season - though it will be the first time the Brazilian will have come home first.
Lap 49 Barrichello is the only driver to opt for a three-stop strategy after he started on dry tyres in wet conditions but he has still managed to master the Monza circuit.
Lap 48 Barrichello is on course to win his first race of the season as he cruises round in his Ferrari, while 0.7 seconds separates the duelling Coulthard and Pizzonia.
Lap 47 Coulthard and Pizzonia are having the best battle down the field for sixth and seventh spot as Barrichello powers on to try and seize his first title of the season.
Lap 46 Barrichello now faces a fight with world champion Schumacher for the victory in Monza and he sees his lead reduced to just 1.9 seconds.
Lap 45 Button and Sato sees their BAR's settle into third and fourth place respectively as they are unable to challenge the pace of the Ferraris.
Lap 44 The Brazilian Ferrari driver has a lead of 3.2 seconds over Schumacher and Button finds his car is simply not fast enough as he settles down in third place.
Lap 43 A Ferrari one-two now seems likely as Barrichello returns to the lead with his relentless pace while Schumacher continues his astounding drive in Monza.
Lap 42 Barrichello goes into the pits and comes out into the straight as his team-mate Schumacher battled it out with Button for second place.
Lap 41 Alonso spins out of the race into the gravel on the second chichane and he surrenders his second place. The Spaniard wanted to be pushed back into the race by the officials but they would not help him.
Lap 40 Schumacher continues to pile the pressure on Alonso and Button while Ferrari team-mate Barrichello is also flying from the front.
Lap 39 Barrichello is expected to make another stop as Button aims to retake the lead.
Lap 38 BAR will hoping Sato would be able to help hold off Schumacher but the Ferrari world champion is staging a major fight back.
Lap 37 Schumacher goes into the pits and battles with Sato as he rejoins the race but crucially he is able to come back out in front of Button's team-mate.
Lap 36 Pantano retires in his Jordan while news from the pits finds Bruni receiving treatment after a fire during his earlier pit stop.
Lap 35 Schumacher takes the lead for the first time in the race as the trio of front runners pit but the German has yet to come in again.
Lap 34 Schumacher piles on the pressure again as he scorches to another fastest lap of 1.21.535 while Button comes into pit and comes out in 9.1 seconds.
Lap 33 Alonson, Sato and Montoya all come into the pits with the Renault man fastest out of the pit lane.
Lap 32 The Ferraris are beginning to show just why they are the cars to beat as Barrichello fires the second fastest lap.
Lap 31 Barrichello brings his Ferrari back into the race in sixth spot after his second stop while Bruni also goes into the pits as the action continues at the opposite end of the field.
Lap 30 Button sees his lead over Alonso cut to 1.5 seconds with Montoya just half a second adrift while Sato glides along in fourth.
Lap 29 Barrichello is the first among the leading pack to pit.
Lap 28 Coulthard must begin his good work down from 10th place but ominously it is Schumacher who has set the fastest lap of the race so far at 1:21.899.
Lap 28 Button is beginning to show worrying signs of slowing but his BAR team-mate Sato is beginning to make up ground from his sixth spot.
Lap 27 Coulthard makes a long fuel stop to take him through to the end of the race.
Lap 26 There are just four seconds separating the top four drivers at Monza in a very close race in overcast conditions.
Lap 25 All the key runners have to stop one more time while Coulthard brings down his gap on the lead to 14 seconds.
Lap 24 Pizzonia nicks eighth spot from Webber as he continues to stand in for Ralf Schumacher in the Williams.
Lap 23 Coulthard is beginning to make something of a charge and finding some speed at Monza but he has yet to make a stop.
Lap 22 Fisichella drops out of the points while Webber and Pizzonia engage in a battle for eighth spot.
Lap 21 The race still has not settled down with several drivers still in contention.
Lap 20 Webber is not able to hold off Schumacher as he jumps up into eighth place. Meanwhile, at the front Button continues to hold a 2.8 second lead over Alonso.
Lap 19 Ferrari's world champion is continuing his pursuit of the leaders and tries to make a move round the first Lesmos turn but he Webber does well to hold him off.
Lap 18 Schumacher is down in 10th place while Coulthard, who appeared to be struggling with his McLaren is down in seventh. Button, Montoya and Alonso continue to battle it out for the lead.
Lap 17 Pizzonia brings his Williams into the pit-lane while Button opens up a 2.6 second lead over Alonso while Montoya is 1.9 seconds further back in thrid.
Lap 16 The German decides not to gamble on passing Button and pits, re-emerging onto the track in 15th place. The Briton, full of fuel, retains the lead in a fast and furious race in Monza.
Lap 15 Button pits for the first time and Schumacher continues to move up the field but he has yet to stop yet.
Lap 14 Raikkonen comes into the pits and he has to retire as a lot of smoke is coming out the back of his car so he will not be able to build on his success last time out in Belgium. It is the eighth retirement of his season.
Lap 13 The German seven-time world champion is preparing to stage something of a fightback as he is blistering down the Monza track.
Lap 12 Schumacher moves up into ninth place as he overtakes team-mate Barrichello down the field.
Lap 11 Alonso comes into the pits as Montoya sets the fastest lap of the race as Coulthard slips to 14th.
Lap 10 Alonso sees his lead cut by Britain's Button to just two seconds.
Lap Nine Trulli is building up some good speed over the opening sector of the track.
Lap Eight Massa's early good work is undone as he has to come in to the pits after losing the nose of his car. Panis suffered the same fate in the opening lap of the race.
Lap Seven Barrichello rejoins the race in ninth spot after being the first driver to pit during the race.
Lap Six Alonso in the Renault opens up a six-second lead over the field as more drivers make their first pit stops. Button moves up to second spot ahead of Montoya.
Lap Five Alonso skips past Barrichello with ease as the Brazilian goe into the pits to swap for dry tyres. Schumacher is battling it out with Coulthard - who was not able to refuel - down the field for 13th and 14th place.
Lap Four Button moves closer to Montoya as the Colombian is overly cautious. Barichello builds up a big lead but he will have to pit soon to change tyres, giving Alonso his chance.
Lap Three The BARs make leaps up the grid as Schumacher is having to fight his way up the field.
Lap Two: Barrichello builds up a seven-second lead at the front in Monza as Ferrari team-mate Schumacher slides back to 15th.
Lap One: Barrichello gets off to a brilliant start and Alonso skips past Montoya to second while Schumacher goes fourth. The two BARs also get off to an aggressive start.
At the first chichane Schumacher spins and Olivier Panis retires from the Grand Prix after just one lap.
David Coulthard has dived into the pits to put on dry tyres so will start from the pits.
1300: Rubens Barrichello leads off the parade lap in front of the home Ferrari fans as the drivers have opted for a mixture of dry and wet tyres. Barrichello is on wets while Michael Schumacher has gone for dry Bridgestones.
1249: The teams have to decide whether to swap from dry to wet tyres at the first opportunity to pit but the track is now expected to dry out quite quickly.
Jordan's Nick Heidfeld is already in the pits so it is uncertain whether he will start.
1235: The drivers are preparing for the 15th Grand Prix of the season in damp conditions in Monza. The circuit can be dangerous in the wet especially under the trees in the Lesmos areas but the sun is coming out.