ARSENAL defender Thomas Vermaelen will be assessed today after coming off with a calf problem towards the end of the Carling Cup defeat of Bolton.
The Belgium international started last night's 2-1 fourth-round win after two months out with an Achilles injury, playing 84 minutes at the Emirates Stadium before being replaced by debutant Daniel Boateng.
Wenger revealed Vermaelen requested to be taken off after a problem in his calf and, while not overly concerned about the seriousness of the injury, expects him to be short of fitness for this weekend's Premier League clash with Chelsea.
"He did very well but he had to come off for a calf problem," Wenger said. "I hope it is not too bad.
"He will be a bit short for Saturday. I do not know yet what has happened.
He added: "I don't think it is a calf strain, I think it is just a tight calf because he has not played 90 minutes for three months."
While Arsenal secured progression to the quarter-finals, they had to withstand a barrage of Bolton pressure to hold out for victory.
Trotters manager Owen Coyle felt disappointed with the result but was proud of his side's effort in north London.
"We scored a very good goal to put us in front and looked to be the team in the ascendancy.
"Then, from my end, the disappointing thing is as good as Arsenal's finishes were, they could have been avoided.
"I thought (Andrey) Arshavin should have been closed down and we paid a heavy cost for that.
"Then we gave the ball away cheaply and got punished by (Chu-Young) Park with a sublime finish."