Arsene Wenger says Arsenal have to win their clash with Manchester United on Saturday after suffering defeat at the hands of Stoke City and dropping points against north London rivals Spurs.

The Gunners suffered their third defeat of the season against Stoke at the weekend, a defeat that cast serious doubts over their chances of mounting a title challenge this season.

Now Wenger realises that they cannot make many more slip-ups, starting with the visit of United to the Emirates Stadium.

"I don't know how many more defeats we can afford," he said. "It's very difficult to say.

"We first have to win our next game and we have a chance again when we play Manchester United on Saturday.

"There is no better game in which to come back from a defeat and from a confidence point of view. It will also give us a chance to show we have quality."

"Is it a game we can't afford to lose? What manager would tell you they can afford to lose a game? You can never afford to lose but we just want to win."

Arsenal have a number of injury concerns ahead of that game, with Theo Walcott and Emmanuel Adebayor limping out of the Stoke defeat. Add to that Robin van Persie's suspension following his red card at the Britannia Stadium, and there are plenty of worries for Arsene Wenger.

However, the state of his squad is apparently not his primary concern at the moment. Wenger told the Arsenal official website: "My biggest worry is that we did not create a lot. We are not used to playing without creating chances and that is very frustrating.

"They scored on two throws and I know you never want that. But we could not express our strong side in the game, which is to create chances and get them out of position.

"I don't approve or disapprove [of Stoke's tactics]. They played the game they wanted and they played it very well. At the end of the day, they could express their strong points and we could not."