LONDON -- Arsenal midfielder Alex Oxlade-Chamberlain will be out for several weeks with a "quite serious" knee injury, manager Arsene Wenger has said.
Oxlade-Chamberlain was hurt in a heavy collision with Barcelona's Javier Mascherano in the first half of the Gunners' 2-0 Champions League defeat at the Emirates on Tuesday.
He was undergoing scans on Friday to determine the extent of the problem.
But Wenger told a news conference ahead of his side's trip to Manchester United on Sunday: "His injury is quite serious and keeps him out for a few weeks.
"He is consulting a specialist. He has injured his knee. Hopefully we will have good news, but he's out for a few weeks. How long exactly, I don't know."
Oxlade-Chamberlain tried to play on after half-time but limped off, and Wenger added: "Let's hope that we get good news and that it's only two or three weeks and not six or seven."
Arsenal remain hopeful that he has not suffered ligament damage in the challenge, which Wenger said had seen him "cut in two by Mascherano."
But the manager stressed: "I don't think it was a malicious tackle. It was a fully committed tackle, but it didn't look malicious."
Wenger also confirmed that defender Gabriel Paulista would have fitness tests on Friday and Saturday to see whether he will be after missing three games with a hamstring injury.