A tough period got much tougher for Arsenal after they were beaten 3-2 by West Ham at Highbury on Wednesday night.
Arsène Wenger's side created a number of chances at the start of each half but, midway through the opening period, Nigel Reo-Coker and Bobby Zamora punished defensive slips.
Thierry Henry touched in a shot from Robert Pires' shot just before the break. Just after it, Arsenal were forced use their second stand-in full back as part of an already injury-hit defence.
They poured forward after the break but, to their credit, West Ham weathered the storm. Matthew Etherington grabbed their third with 10 minute to go and, although Pires thumped home from close range 80 seconds from the end of normal time, the visitors held on.
It was not the way to celebrate Arsenal's 2000th match at Highbury.
Wenger's men are still playing catch-up in the race for Champions League qualification.
Before kick-off, the manager welcomed back Gilberto (calf), Henry (hamstring), Dennis Bergkamp and Pires (both rested) after they had missed Saturday's FA Cup exit at Bolton.
However he was forced to field the inexperienced back four from the weekend. On the eve of the game Lauren joined an injury list that already comprised Ashley Cole (thigh), Gael Clichy (foot), Pascal Cygan (hamstring), Emmanuel Eboue and Kolo Toure (all African Nations Cup). The right back has a swollen knee and is likely to be out for a month.
In addition Jose Antonio Reyes and Francesc Fabregas were suspended while Manuel Almunia made way for Jens Lehmann.
The traffic was one-way in the opening stages. In the fifth minute, Abou Diaby reached the by-line and chipped the ball to Henry on the penalty spot.
The striker had time and space to pick his shot but his side foot volley hit Freddie Ljungberg who was standing three yards from goal. It was probable but not certain the shot would have beaten West Ham keeper Shaka Hislop
Two minutes later, Van Persie received the ball at the near post and tricked himself some space. He unleashed a rasping shot that beat Hislop but bounced off the outside of the post.
At this point an Arsenal goal seemed imminent.
The flow of chances dried up as the game wore on but the pressure was still coming from the home side.
Midway through the half, Ljungberg's chip sent the Dutchman clear for a second but he could not control the ball and Anton Ferdinand cleared the danger
Play went up the other end and Yossi Benayoun trickled a shot at Lehmann. It was West Ham's first opportunity of the game.
However they were to take the lead within a of couple minutes. Etherington sent a ball through for Reo-Coker and the midfielder touched the ball onto Campbell's foot. It fell kindly for the West Ham captain to race through and plant the ball past Jens Lehmann.
Highbury was stunned. They would be stunned again in the 32nd minute but, before that, Arsenal were to suffer two further blows.
First, there was a decent shout for a penalty when Paul Konchesky appeared to handle a cross from the left.
Then Wenger was forced to replace the hobbling Kerrea Gilbert with Mathieu Flamini. All the fit defenders in the squad had started the game so the midfielder had to fill-in at right back.
West Ham's second followed straight away. Zamora cleverly controlled a lofted through ball with his chest and shrugged off Campbell's challenge. The former Brighton striker then had ample time and space to steer his shot into far corner of the net.
It was an incredible turnaround in a game that had seemed Arsenal's for the taking in the opening stages.
The home side seemed to struggle to cope with what had happened to them. But crucially they roused themselves before the break.
Two minutes from half-time, Henry and Djourou had shots kicked off the goal-line after Diaby flicked the ball into the penalty area.
On the whistle, Arsenal finally scored. Robin van Persie's acutely angled shot was booted off the line. Pires returned the ball with interest and Henry touched the ball past the covering defenders. It was his 151st League goal, beating Cliff Bastin's Arsenal record. It also took him one goal away from becoming the first player to scored 200 goals for the club.
Despite all that, Arsenal still had it all to do as the second half started. And they would have to do without Campbell, who did not appear after the restart. Sebastian Larsson came on at left back with Senderos moving to the centre. The Swede was Arsenal's seventh player to fill that position this term.
The change meant that Wenger's back line - Larsson (21), Senderos (21), Djourou (19), Flamini (22) - now had a combined age of 83. Or just over two Teddy Sheringhams if you like. The ex-Tottenham was on the bench tonight for the visitors.
Despite their inexperience Arsenal again started the half at pace. Pires drove a rising effort over the bar and, just before the hour, Ljungberg darted to the byline only to see his shot blocked at the near post by Hislop.
A couple of minutes later Ferdinand fouled Henry just outside the area and Van Persie's low, deflected free-kick nearly crept in at the far post.
Arsenal tails were up, the crowd were backing them and they were pushing West Ham back. The only danger seemed to be over-eagerness in defence and being caught on the break.
In the 65th minute, Henry nearly got the home side on level terms when he won the ball on the left-hand by-line and nearly curled his shot across the face of goal into the far corner.
However, West Ham were looking increasingly comfortable. So Wenger responded by replacing Diaby with Bergkamp and switching to 4-3-3.
The killer goal arrived with 11 minutes left. Reo-Coker won the ball on the right and crossed to the far side. Etherington collected the ball and his shot deflected off Djourou so all Pires, stationed on the line, could do was boot the ball high into the net.
Arsenal tried to respond. Henry sent a spectacular overhead kick just wide and Pires sent a drive inches beyond the same post.
The latter Frenchman thumped home with just over a minute left after Hislop had spilled Bergkamp's shot.
The final seconds, like the game before them, were enthralling but ultimately disappointing.
- Campbell 45
- Gilbert 27
- Pires Goal!
- Diaby 71
- Henry Goal!
- Larsson 45 Yellow Card
- Flamini 27
- Bergkamp 71
West Ham United
- Clarke 76
- Gabbidon Yellow Card
- Benayoun 66
- Reo-Coker Goal!
- Etherington Goal!
- Zamora 73 Goal!
- Fletcher 76
- Newton 66
- Ashton 73