Petr Cech will miss the next three to four weeks with a "serious calf injury."

Cech was injured in the last moments of Wednesday's 2-1 loss to Swansea when he ran up the pitch for a corner as the Gunners pushed for an equalizer.

Arsene Wenger said Cech also had a minor groin injury before the game that may have hampered him as well, but that he did not regret the decision to play him.

"He declared himself 100 percent fit [before the game], and then you have to trust the player," Wenger told a news conference. "He's 33 years old, and he knows his body.

"You want the players to be tough enough to play sometimes through little pains because you're never completely perfect in March before a game. So he took that very well, and I respect that."