London - Arsenal manager Arsene Wenger has confirmed that key midfielder Santi Cazorla has undergone knee surgery and will be sidelined for up to four months.
The 30-year-old Spain international was injured early in the second half of Arsenal's draw at Norwich last weekend, but remained on the pitch for the rest of the game.
It was unclear at first whether or not the former Malaga star would have to go under the knife.
But in the aftermath of Saturday's 3-1 win over Sunderland, Wenger confirmed that Cazorla will be missing until March after having surgery on a ruptured ligament on Friday.
"We know now. It has happened already. It's not the season. It is at least three months, maybe four," said the Frenchman.
"Santi wanted to have a chance to come back quickly so he didn't want to last too long for 25 opinions and he decided to go straight away.
"The guy said, 'look it's a clear case, it's a rupture of the external knee ligament'. And he said 'Okay, let's do it straight away.'"
Cazorla's misfortune could be a blessing in disguise for Aaron Ramsey who has been keen to play in the Spaniard's central midfield role.
"I prefer to be back in the middle of the pitch, that is where I feel more comfortable and feel like I play my best football," said Ramsey who scored in Saturday's win.
"I wish Santi a speedy recovery - we have been hit hard by injuries this season but it gives players the opportunities to take.
"I have made no secret that I prefer to play in the middle and hopefully now I can stay there."