Laurent Koscielny had given the Gunners the lead but following a second-half sending off for Johan Djourou, Steve Sidwell equalised and Bobby Zamora scored right at the death to complete the comeback.
A disappointed Szczesny felt that the north Londoners should have left Fulham with all three points and he blamed his side’s poor defending.
“There was probably some tired legs, but I think probably we should have kept the concentration and kept the focus and we would have been fine,” he told reporters.
“But I would imagine it was a very childish performance in the end from us. It was very confusing.
“I thought for 85 minutes we defended really well with 11 men and they never looked like
scoring and then, when we had to play with 10 men, they looked very dangerous.
“I’m very disappointed with the result, but hopefully we can recover as soon as possible. The fixtures come thick and fast and players get tired and these kind of results can happen.
“We were hoping to take advantage of that. We felt we could do so and were disappointed, so hopefully in the coming weeks we can do much better.”
Szczesny also criticised referee Lee Probert, who failed to give a penalty in the first half for a Philippe Senderos challenge on Gervinho and later gave Djourou a second yellow card for fouling Zamora.
“Johan said he barely touched him. The guy [Zamora] seemed to go down very easy. Plus I had the ball in my hands already, which doesn’t help. After Johan got sent off, it was very difficult for us,” he said.
“I didn’t see [the penalty shout] from my end but from what the lads said in the dressing room it wasn’t a penalty claim - it was just a clear penalty. It seems like we don’t get those decisions these days but, hopefully, next time they’ll come for us.”
Arsenal legend Thierry Henry looks like he will return for a two-month loan and could be available for next Monday’s FA Cup tie against Leeds United.
Henry has been training with the Gunners since the end of the MLS season and Szczesny hopes that he soon gets the chance to step on to the pitch in a competitive game.
“He’s quality,” added Szczesny.
“He’s a great finisher and he’s very clever, very intelligent, plus he’s a great figure to have in the dressing room. He helps all the players off the pitch, as well as on the pitch. So it’s great to have him in the dressing room.
"Hopefully everything will be done and confirmed as soon as possible because we need him.”
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