Arsene Wenger believes one goal in Rome will be enough to put Arsenal through to the last eight of the Champions League. Robin van Persie s first-half penalty, awarded after the Dutchman was tripped by Philippe Mexes, was all the Gunners had to show after

Arsene Wenger believes one goal in Rome will be enough to put Arsenal through to the last eight of the Champions League.

Robin van Persie's first-half penalty, awarded after the Dutchman was tripped by Philippe Mexes, was all the Gunners had to show after dominating AS Roma in their 1-0 Champions League first-leg win at Emirates on Tuesday evening.

Nicklas Bendtner wasted two opportunities to double the lead while Emmanuel Eboue also squandered a great chance - and they were nearly punished when John Arne Riise came within a whisker of equalising for Luciano Spalleti's side.

Wenger believes van Persie's goal, coupled with an invaluable clean sheet - Arsenal's fifth in a row in all competitions - puts the Gunners in the driving seat ahead of the second-leg on March 11.

"If we score once that should be enough," said the Arsenal manager.

"I'm happy with our performance but there was room to score more. You never know what a good result is in the European Cup ... in the first 20 minutes of the second half we had one chance after another.

"There was room to score more but one of the positives is we didn't concede a goal. The next game will be interesting because they'll throw much more forward."

Abou Diaby is a doubt for Saturday's Barclays Premier League home game with Fulham after limping out of the Roma clash with a calf strain.

Wenger says his injury-hit squad will have to cope between now and the return in Rome.

"We have three more games between this tie and the second leg. At the speed we lose players it can be difficult for us," Wenger moaned.

"I'm scared we lost Diaby because he has a calf problem. Will anybody we back (for Rome)? We don't know. It could be Adebayor, maybe Eduardo ... but we are short in midfield at the moment."

Arsenal were embarrassed after starting the second half on Tuesday night with only nine men when Kolo Toure and William Gallas failed to reappear.

Referee Claus Bo Larsen then booked Toure for running on the pitch after the game restarted.

"Kolo always goes out last," explained an annoyed Wenger. "He waited for William, but didn't know William had treatment.

"He didn't know the game had started without them. He was putting on his boots. I don't know if it is superstition. It's our fault. You have to be ready when the bell rings."

Roma coach Spalletti said Arsenal deserved the victory, but promised a different outcome at the Stadio Olimpico.

"I think it is a fair result. I feel confident that we have the same chances as Arsenal. We will have more chances in the second leg. I'm sure that will be a completely different match. Roma will be completely different."

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