The England international looked to have tweaked the muscle in his leg when defending against the Chelsea left-back Ryan Bertrand in their 0-0 draw with Blues on Saturday, but played on for five minutes until he was forced off.

And Wenger revealed that the injury could be one that rules him out for the last three games of the season, against Stoke, Norwich and West Brom.

"Theo looks to have a serious hamstring (injury)," Wenger told reporters.

"He wanted to stay on. It will be tough to come back this season."

Wenger was disappointed not to win the 'strange' game, after his side enjoyed the better chances, striking the woodwork through both captain Robin van Persie and defender Laurent Koscielny.

"(It was a) strange game. They decided to lock the game up and catch us on the break. On that front, especially with the two wide players, they tried to get over the top of our full-backs and waited for us in their half of the pitch," Wenger said.

"We were not quick enough with our passing today to open them up. Therefore, you always felt the game was a bit difficult. We lacked a bit of a spontaneous aspect in our game. But we still had chances to win the game, and they had zero. They had none.

"We certainly had the better of the chances because I can't remember them having one clear-cut chance. I expected the game to be very open because they had to win and we had to win but that shows you how unpredictable football is."

Wenger admitted their Champions League fortunes remain in doubt, and stated that his team had not fully moved on from the shock 2-1 home defeat to Wigan.

He said: "I don't know what it does for the Champions League places. It depends on results over the weekend and over the next three games.

"I don't think the result on Monday night (against Wigan) had been completely digested. At least today we didn't lose, and that solid defensive base is something we can use to have a strong finish."

Chelsea interim boss Roberto Di Matteo was delighted with an away point, stating that their final touch was the only thing that let them down.

"I think it was a brilliant team performance by ourselves. When you come to the Emirates it's difficult to play against Arsenal," he told Sky Sports.

"We got ourselves in some good positions but the final pass was missing a little bit. But I thought it was a fantastic performance.

"The organisation, the team spirit, the effort, the commitment, from everybody, we had a lot of changes today and everybody showed that they are Chelsea players."

Di Matteo said his men would continue to push for the final Champions League spot, despite having endured a packed schedule of late.

"This was our third game in less than six days. It's absolutely incredible, the demand on these players. The way they've responded to this fixture list personally I think is crazy. But we showed there's a great, great quality in this team and the spirit is very high," the Italian said.

"It keeps our momentum going and the confidence high and the belief that we are getting better and better. We can achieve any result that we want and it's a great squad that we have. We go into the next game again with the belief that we can qualify."