Alex Song is a major doubt for Arsenal's Champions League tie with Shakhtar Donetsk tomorrow after limping out of training this morning.
The Cameroon midfielder was Arsenal's hero on Saturday as he scored a last-gasp winner against West Ham.
But Song, who was already a doubt for the clash in the Ukraine, gave Arsene Wenger another headache when he pulled up while jogging as Arsenal trained at their London Colney base.
The 23-year-old received treatment before limping off the pitch, and it is unclear whether he will even travel to face the Ukrainian champions, who Arsenal beat 5-1 two weeks ago.
Arsenal have already confirmed they will be without skipper Cesc Fabregas for the Group H clash.
The midfielder is struggling with a hamstring injury and will not be risked by Gunners boss Arsene Wenger ahead of the home match against Newcastle at the weekend.
"He has a good chance to play on Sunday but Wednesday night is too risky," said Wenger. "He has no real strain, just a bit of pain.
"I don't know what it's down to but we cannot take a gamble as he has had injuries before. There's still a bit of reluctance to push it 100%."