By Chris Harris
A late, late strike from Dennis Bergkamp snatched victory for Arsenal in their Champions League opener at Highbury.
The Dutch master prodded past Eldin Jakupovic in stoppage time to end Thun's brave resistance when it seemed the Swiss minnows would head home with an unlikely point.
On the evidence of the first 91 minutes, it looked like Lady Luck was frowning at Arsenal. They dominated but a harsh red card for Robin van Persie, and then a freakish equaliser, looked like thwarting them.
Van Persie was dismissed on the stroke of half-time after accidentally catching Alen Orman with a high boot. Arsenal regrouped and Gilberto nodded them ahead early in the second half.
The clever money was on Arsenal at that stage but, amazingly, Thun were level within two minutes when Nelson Ferreira's attempted cross looped past Manuel Almunia.
The 10 men huffed and puffed but it didn't look like their night. Then Bergkamp popped up in the dying seconds.
The big team news before kick-off concerned Sol Campbell. The England defender has played just twice since the first day of February but led Arsenal out for his first appearance this season.
Campbell was one of five changes to the team which started Saturday's 2-1 defeat at Middlesbrough. Two were enforced: Jens Lehmann began a two-match UEFA suspension so Manuel Almunia deputised, and Cesc Fabregas replaced the injured Mathieu Flamini.
Elsewhere, Van Persie and Freddie Ljungberg were drafted in. Out went Pascal Cygan, Alexander Hleb and Bergkamp. The other notable absentee was Thierry Henry, ruled out for up to six weeks with a groin injury.
Arsenal are old hands at this Champions League lark but this is Thun's first adventure in Europe's premier competition. They were playing amateur football as recently as seven years ago but are clearly no slouches. Just ask Dynamo Kiev and Malmo, who both fell victim to the Swiss minnows in the qualifying rounds.
Arsenal were a different matter. Stung by Saturday's defeat at Middlesbrough and heeding Wenger's demand for a suitable response, they were quickly into their stride.
The chances flowed. Robert Pires skipped inside two defenders before curling a beauty just wide of the far post, Van Persie's fierce shot was parried and Kolo Toure was inches away from connecting with Pires' dinked free-kick. That was just the opening 10 minutes.
Thun were a sporadic threat. Almunia had to race out and grasp the ball as Faria Adriano got behind the Arsenal defence. Otherwise, the Swiss side were limited to a few teasing crosses which required the attention of Campbell and Kolo Toure.
Toure was soon in action down the other end too. One of these days he is going to rip the net out with a free-kick but his latest vicious effort - from all of 25 yards - was palmed away by the keeper.
Reyes was next to try his luck. His fizzing effort bounced awkwardly for Jakupovic but Thun were able to clear the danger.
It all boded well for Arsenal. They have been accused of over-elaborating in the past but, with Reyes and Ljungberg providing width, Van Persie prepared to attack the six-yard box and a shoot-on-sight policy, the Gunners looked potent.
Reyes' partnership with Van Persie - which blossomed when Henry was injured at the end of last season - continued to prosper. Just after the half-hour mark the Spaniard sprinted down the left and crossed low. Only a timely intervention by Ljubo Milicevic denied Van Persie a tap-in.
Arsenal went even closer two minutes before the break when Jakupovic allowed Reyes' low shot through his legs. The ball rolled agonisingly towards the goal-line but Thun were awarded a free-kick as Ljungberg charged in to challenge the keeper.
A minute later, the referee made an even more decisive decision. Van Persie attempted to control a high ball with his foot but accidentally caught Orman in the face as the Thun defender tried to head clear. There was no malice, there was no intent - but the card was red.
Suddenly, the complexion of the game changed. Arsenal had dominated up until that point but, as they emerged for the second half, the task in hand looked significantly tougher.
Six minutes later, those fears were allayed. Reyes whipped a corner in from the right flank and Gilberto soared at the far post to nod the ball beyond Jakupovic and into the corner.
Highbury breathed a sigh of relief but there was an immediate twist in the tale. Thun, pretty much redundant as an attacking force until then, pushed forward menacingly.
A deep cross from the right was half-cleared by Toure and bounced towards Ferreira, who attempted to hook the ball into the six-yard box with his back to goal. Instead, his attempted cross looped in at the far post. A freak goal and a real hammerblow for the 10 men.
Arsenal were clearly shellshocked and Tiago Bernardi almost took advantage, shooting wastefully over the bar after taking up a great position in the penalty area.
The hosts regrouped. Ljungberg prodded the ball past the keeper but wide of the post after being played through. Reyes and Pires both went close but they couldn't find a way through.
On came Bergkamp and Quincy was not far behind. Toure nodded just wide three minutes from time with the keeper stranded but the game seemed to be up for Arsenal.
It wasn't. Bergkamp showed great strength to win the ball inside Thun's penalty area and he poked the ball into the bottom corner to send Highbury into raptures.
Referee: Grzegorz Gilewski
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