Tamas Priskin scored as struggling Ipswich Town stunned Arsenal to deservedly win the first leg of their Carling Cup semi-final at Portman Road.
Arsenal had struggled against Championship opposition when they were held by Leeds United in the third round of the FA Cup on Saturday - and they again found it difficult against a side from the second tier.
The decisive goal came in the 78th minute when Priskin ran on to a through ball from Colin Healy and took one touch before drilling his strike into the bottom corner beyond Gunners goalkeeper Wojciech Szczesny.
And it would have got even worse for Arsenal manager Arsene Wenger's team had Szczesny not saved a late effort from Carlos Edwards.
Ipswich keeper Marton Fulop twice saved from Theo Walcott and Gunners captain Cesc Fabregas failed to convert a cross that dropped invitingly inside the six-yard box, but across the 90 minutes the visitors had precious little to show for their efforts.
McParland knew Arsenal would not score
The Tractor Boys had been thrashed 7-0 by Chelsea in the FA Cup on Sunday, lie 19th in the Championship and had caretaker boss Ian McParland in charge after sacking manager Roy Keane last Friday.
But with new boss Paul Jewell watching from the stands before taking charge of the team on Thursday, the home side belied a run of form that had seen them lose eight of their last 11 fixtures with a performance of tremendous desire and determination.
Ipswich grew in confidence as the match wore on, received tremendous support from the sold-out Portman Road crowd of 29,146 and will deservedly take their slender lead into the second-leg at Emirates Stadium on Tuesday 25 January.
The Suffolk side lined up with the dangerous Connor Wickham on the left side of a five-man midfield as Town successfully stymied their Premier League opponents.
Arsenal, hoping to use the Carling Cup to end a six-year wait for a trophy, threatened in the opening minutes and Fabregas was inches from connecting with a square pass from the largely ineffectual Andrey Arshavin.
Midway through the opening half, Ipswich midfielder Edwards inadvertently forced keeper Fulop into action with a looping header towards his own goal.
But the north Londoners, despite the presence of Fabregas, Arshavin, Walcott and Jack Wilshere in their starting XI, were poor and their Championship opponents grew in confidence as the match wore on.
Arsenal full-back Kieran Gibbs made a decent block from a shot by Edwards after 15 minutes, while Priskin went close with a vicious strike across goal after picking up the ball on the left and cutting inside just after the half-hour mark.
The home side created a flurry of half-chances close to the break, the most notable of which came when Wickham showed great skill to create the space to cross from the left but skipper David Norris could not quite connect with his attempted header
Priskin had the ball in the net with a spectacular overhead volley but he was offside and the Hungarian striker missed with a long-range strike as Ipswich worked up a head of steam against a sluggish Arsenal side.
And the hosts continued to play on the front foot after the restart, with veteran Mark Kennedy exemplifying the surging self-belief by attempting to chip Szczesny from close to the halfway line.
In contrast, Arsenal's flagging form was epitomised when the disappointing Denilson played team-mate Laurent Koscielny into trouble with a weak pass across the face of his team's penalty area.
Arshavin shot wide from the edge of the box in a rare opening for the Gunners, while at the other end it took a last-ditch clearance from Johan Djourou to deny Priskin after a long-ball upfield from Jaime Peters unlocked the visiting team's defence.
Wenger remains confident despite defeat
Prior to conceding, the north Londoners had finally started to build some pressure, with Fulop smothering a Walcott effort from a tight angle and Fabregas failing to convert Gibbs's cross.
The goal came when another ball over the top caught out the Gunners, with Priskin's crisp low finish no less than his team deserved.
Wenger's men had 12 minutes of normal time to find an equaliser but Fulop again denied Walcott as Ipswich closed out the match to give themselves a lead to defend in the second leg.
Highlights of the first leg of Ipswich and Arsenal's Carling Cup semi-final will be on BBC Sport website from 2200 GMT on Thursday.
90:00+3:21 The assistant referee signals for offside against Connor Wickham. Wojciech Szczesny takes the indirect free kick.
90:00+2:18 Theo Walcott challenges Damien Delaney unfairly and gives away a free kick. Marton Fulop takes the direct free kick.
90:00+1:40 Francesc Fabregas takes a shot. Blocked by Gareth McAuley.
90:00+1:05 David Norris challenges Neves Denilson unfairly and gives away a free kick. Laurent Koscielny takes the direct free kick.
90:00+0:25 Free kick awarded for an unfair challenge on Jaime Peters by Carlos Alberto Vela. Free kick taken by Marton Fulop.
89:24 Unfair challenge on Neves Denilson by Colin Healy results in a free kick. Emmanuel Eboue restarts play with the free kick.
89:24 Substitution Ronan Murray is brought on as a substitute for Tamas Priskin.
88:10 Carlos Edwards takes a outswinging corner from the right by-line to the near post, clearance made by Francesc Fabregas.
87:48 Carlos Edwards takes a shot. Wojciech Szczesny makes a save.
87:27 The ball is crossed by Francesc Fabregas, save by Marton Fulop.
87:04 Francesc Fabregas takes the inswinging corner, clearance made by David Norris.
85:37 Kieran Gibbs delivers the ball, blocked by Darren O'Dea.
85:00 Inswinging corner taken from the left by-line by Francesc Fabregas, Connor Wickham makes a clearance.
84:49 Theo Walcott takes a shot. Save by Marton Fulop.
84:34 Tamas Priskin is ruled offside. Free kick taken by Wojciech Szczesny.
84:08 Marouane Chamakh takes a shot. Save by Marton Fulop.
83:42 Corner from the left by-line taken by Theo Walcott, clearance made by Mark Kennedy.
82:59 Connor Wickham gives away a free kick for an unfair challenge on Theo Walcott. Francesc Fabregas delivers the ball from the
free kick right-footed from right wing, Darren O'Dea manages to make a clearance.
82:13 The ball is crossed by Alex Song.
81:12 Laurent Koscielny fouled by Tamas Priskin, the ref awards a free kick. Laurent Koscielny restarts play with the free kick.
81:12 Booking Tamas Priskin goes into the referee's book for unsporting behaviour.
79:48 Substitution Andrey Arshavin goes off and Carlos Alberto Vela comes on.
79:37 Theo Walcott takes a shot. Damien Delaney gets a block in.
77:20 Colin Healy provided the assist for the goal.
77:20 GOAL - Tamas Priskin:Ipswich 1 - 0 Arsenal Tamas Priskin gets on the score sheet with a goal from inside the penalty area to the bottom right corner of the goal. Ipswich
75:22 The ball is crossed by Kieran Gibbs, Shot by Francesc Fabregas from inside the six-yard box clear the bar.
72:45 Free kick awarded for an unfair challenge on Damien Delaney by Marouane Chamakh. Marton Fulop restarts play with the free
70:33 Outswinging corner taken right-footed by Andrey Arshavin, clearance made by David Norris.
70:22 Theo Walcott takes a shot. Save made by Marton Fulop.
69:36 Theo Walcott takes a shot. Save by Marton Fulop.
68:54 Kieran Gibbs crosses the ball, clearance made by Gareth McAuley.
67:20 Long distance shot from Kieran Gibbs misses to the left of the goal.
67:20 Substitution Alex Song on for Jack Wilshere.
66:14 Connor Wickham gives away a free kick for an unfair challenge on Neves Denilson. Emmanuel Eboue takes the free kick.
64:25 Jack Wilshere concedes a free kick for a foul on David Norris. Mark Kennedy takes the direct free kick.
63:02 Connor Wickham has an effort at goal from just outside the box which goes wide of the left-hand upright.
62:19 Outswinging corner taken left-footed by Mark Kennedy from the left by-line, Darren O'Dea takes a shot.
62:13 Darren O'Dea crosses the ball, clearance by Johan Djourou.
61:28 Corner taken left-footed by Mark Kennedy, clearance made by Francesc Fabregas.
58:42 Tamas Priskin takes a shot. Wojciech Szczesny makes a save.
58:01 Corner taken by Andrey Arshavin from the left by-line played to the near post, clearance made by Connor Wickham.
56:00 The ball is sent over by Andrey Arshavin, save made by Marton Fulop.
55:41 Theo Walcott crosses the ball, blocked by Damien Delaney.
55:19 The referee blows for offside. Free kick taken by Laurent Koscielny.
54:22 Lobbed left-footed shot by Mark Kennedy. Save by Wojciech Szczesny.
53:21 Free kick awarded for an unfair challenge on Theo Walcott by Damien Delaney. Free kick taken by Johan Djourou.
52:53 Connor Wickham takes a shot. Blocked by Emmanuel Eboue.
52:45 The ball is crossed by Carlos Edwards.
52:40 The ball is delivered by Mark Kennedy.
52:30 A cross is delivered by Connor Wickham, clearance made by Emmanuel Eboue.
51:23 Carlos Edwards crosses the ball.
50:53 Laurent Koscielny challenges Carlos Edwards unfairly and gives away a free kick. Mark Kennedy crosses the ball from the free
kick left-footed from right channel, Laurent Koscielny makes a clearance.
50:09 The assistant referee flags for offside against Colin Healy. Emmanuel Eboue restarts play with the free kick.
49:32 Andrey Arshavin is caught offside. Marton Fulop restarts play with the free kick.
48:46 Shot from deep inside the area by Andrey Arshavin goes over the bar.
47:49 The referee penalises David Norris for handball. Wojciech Szczesny takes the indirect free kick.
47:20 Mark Kennedy fouled by Francesc Fabregas, the ref awards a free kick. Free kick taken by Marton Fulop.
45:01 The match restarts for the second half.
45:00+1:03 It is the end of the first-half.
43:43 Free kick awarded for a foul by Darren O'Dea on Theo Walcott. The free kick is delivered left-footed by Jack Wilshere from
right wing, clearance made by Mark Kennedy.
43:43 Booking Caution for Darren O'Dea.
43:07 Connor Wickham takes a long range shot clearing the crossbar.
42:50 Colin Healy crosses the ball, clearance made by Kieran Gibbs.
41:45 Tamas Priskin is ruled offside. Free kick taken by Wojciech Szczesny.
41:20 Carlos Edwards fouled by Kieran Gibbs, the ref awards a free kick. Direct free kick taken by Mark Kennedy.
39:47 Foul by Laurent Koscielny on David Norris, free kick awarded. Mark Kennedy crosses the ball in from the free kick.
39:17 Centre by Theo Walcott, Gareth McAuley gets a block in.
38:23 The ball is swung over by Connor Wickham.
36:01 Mark Kennedy challenges Emmanuel Eboue unfairly and gives away a free kick. Francesc Fabregas produces a shot on goal direct
from the free kick.
34:05 The ball is delivered by Kieran Gibbs, blocked by Carlos Edwards.
33:56 Theo Walcott sends in a cross.
32:03 Theo Walcott takes a shot. Save by Marton Fulop.
29:47 Outswinging corner taken from the right by-line by Carlos Edwards, Close range header by Gareth McAuley goes over the bar.
29:37 Connor Wickham takes a shot. Jack Wilshere gets a block in.
29:07 Outswinging corner taken right-footed by Carlos Edwards from the right by-line, save by Wojciech Szczesny.
28:56 Mark Kennedy takes a shot. Emmanuel Eboue gets a block in.
27:04 Connor Wickham challenges Emmanuel Eboue unfairly and gives away a free kick. Francesc Fabregas restarts play with the free
26:55 Kieran Gibbs delivers the ball, clearance by Darren O'Dea.
22:31 Corner taken right-footed by Andrey Arshavin, Johan Djourou gives away a free kick for an unfair challenge on Damien Delaney.
Direct free kick taken by Marton Fulop.
22:25 Kieran Gibbs crosses the ball, Gareth McAuley gets a block in.
21:42 Corner taken left-footed by Jack Wilshere.
19:18 Mark Kennedy takes a shot.
17:27 Jack Wilshere delivers the ball, Theo Walcott takes a shot.
16:32 Connor Wickham concedes a free kick for a foul on Emmanuel Eboue. Francesc Fabregas crosses the ball in from the free kick,
Jaime Peters manages to make a clearance.
16:18 The ball is swung over by Theo Walcott.
15:18 Theo Walcott produces a right-footed shot from close range which goes wide of the left-hand upright.
13:42 Tamas Priskin has an effort at goal from just outside the box which goes wide of the right-hand post.
12:49 Carlos Edwards takes a shot. Kieran Gibbs gets a block in.
9:39 Centre by Kieran Gibbs, Neves Denilson takes a shot. Blocked by Colin Healy.
8:01 Unfair challenge on Colin Healy by Jack Wilshere results in a free kick. Marton Fulop restarts play with the free kick.
6:25 Foul by Damien Delaney on Nicklas Bendtner, free kick awarded. A cross is delivered by Francesc Fabregas, Shot by Andrey Arshavin
from deep inside the penalty area misses to the left of the target.
3:01 Outswinging corner taken right-footed by Carlos Edwards, Laurent Koscielny manages to make a clearance.
2:55 The ball is sent over by Carlos Edwards, clearance made by Laurent Koscielny.
2:30 Tamas Priskin concedes a free kick for a foul on Neves Denilson. Francesc Fabregas takes the free kick.
2:04 Colin Healy concedes a free kick for a foul on Theo Walcott. Neves Denilson restarts play with the free kick.
1:32 The ball is crossed by Andrey Arshavin, Mark Kennedy manages to make a clearance.
0:51 Jack Wilshere delivers the ball, save by Marton Fulop.
0:00 The ref blows the whistle to start the match.
Live text and data provided by The Press Association.
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