Stoke's Bojan Krkic will miss the rest of the season after suffering a ruptured cruciate ligament in his left knee.
Bojan sustained the injury in Stoke's FA Cup win over Rochdale.
The Spaniard scored Stoke's first goal in the game, but was forced off in the 32nd minute after collapsing after challenging for the ball.
Scans have revealed the former Barcelona winger suffered a ruptured cruciate ligament in his left knee and will have to undergo surgery.
Stoke boss Mark Hughes said: "It's bitterly disappointing for the club but even more so for Bojan himself as he was making such a big impact on the Premier League and clearly enjoying his football. We wish him a speedy recovery."