Uefa Champions League, Group Phase/Arsenal 2 FC Thun 1: Arsenal's European malaise is growing pathological. So deep does it apparently run that even the easiest group in the Champions League will present a troublesome proposition.

Last night the minnows of Thun, unheard of in these circles before this season, almost proved insurmountable. It took an injury-time goal from the substitute Dennis Bergkamp to put away the Swiss underdogs. Arsenal fans might point to the seeming injustice of Robin van Persie's first-half dismissal but even 10 Premiership millionaires should have made light work of these valiant but limited visitors.

Wenger, who has bemoaned the vogue for five-man midfields that appears almost virulently to have spread from Stamford Bridge, must have been rolling his eyes on noting that last night's opponents also employ lone-striker tactics.

Wenger's complaint that the trend will suffocate the game is more than idle chatter; the Arsenal manager will be concerned that if fans turn away from football in the manner they did in the 1980s, the Emirates Stadium, monument to his club's recent success, might become a financial millstone.

And with that as the backdrop still Arsenal labour to break down 4-5-1 formations. Wenger made five changes to the side that lost at Middlesbrough on Saturday and immediately the team looked stronger - not least for the presence of the returning Sol Campbell, who was awarded the captaincy in only his third Arsenal match since February 2nd.

After surviving an early scare when the ill-timed challenge on Mauro Lustrinelli from the last defender, Kolo Touré, might have prompted a fourth-minute red card from the Polish referee, Arsenal enjoyed the overwhelming share of possession. However, they were restricted to just four meaningful first-half chances by the Swiss league's fifth-placed side.

Touré struck a ferocious free-kick that Eldin Jakupovic did well to parry. Van Persie pulled a reaction stop from his close-range shot shortly after Robert Pires had curled wide from 20 yards out. Cesc Fábregas then played fine passes with Robert Pires and Van Persie that put him into the Thun box but he could only drag his shot wide.

Arsenal did have the ball in Thun's net but only after Freddie Ljungberg bundled Jakupovic over the line after the goalkeeper had allowed José Antonio Reyes's shot to squirm between his legs.

And then came Van Persie's dismissal for a foul that was more misfortune than misdeed. With his eyes focused firmly on the ball the Holland international soared in an attempt to trap it in mid-air but connected with the dipping forehead of Alen Orman, producing plenty of blood to match the red card.

Arsenal fans will have recognised some ironic justice in the goal that came six minutes after the break. Reyes swung in a corner from the right and Gilberto Silva escaped his marker, Orman, to head delectably over Jakupovic; the lead, though, was short-lived. Touré could only half clear with his head and it fell to Nelson Ferreira five yards from the Arsenal box. The left-winger saw Manuel Almunia lingering away from his line and hooked his improbable shot over his own shoulder and under the crossbar.

Arsenal were not happy with the referee's decision to turn down down a penalty that seemed due when the already booked and indisputably inadequate left-back Jose Goncalves bodychecked Reyes.

With the Arsenal fans roused, the home side began to exhibit more urgency. Reyes challenged Jakupovic as he cleared but the ricochet evaded the net.

Then Fábregas attacked the box only to shoot wide. But the best chance fell to Ljungberg as he pounced on a mishit header back to the goalkeeper, lifting his shot over Jakupovic but wide of the post.

As the game appeared to slip away, Wenger reacted drastically, introducing Bergkamp for Fábregas, leaving his team two players light in midfield. However Bergkamp's introduction proved inspired as he showed his undiminished strength against two defenders, spinning before turning his shot past Jakupovic.

ARSENAL: Almunia; Lauren, Toure, Campbell, Cole, Ljungberg (Hleb 80), Silva, Fabregas (Bergkamp 72), Pires, Reyes (Owusu-Abeyie 80), Van Persie. Subs not used: Poom, Song Billong, Clichy, Senderos. Sent off: Van Persie (45). Booked: Toure. Goals: Silva 51, Bergkamp 90.

FC THUN: Jakupovic; Orman, Hodzic, Milicevic, Goncalves, Gerber (Leandro 72), Bernardi, Adriano (Gelson 57), Aegerter, Ferreira, Lustrinelli (Faye 87). Subs not used: Portmann, Duruz, Spadoto. Booked: Hodzic, Goncalves, Ferreira. Goal: Ferreira 53.

Referee: Grzegorz Gilewski (Poland).