Arsene Wenger has admitted that he will have to wait and see whether Arsenal playmaker Henrikh Mkhitaryan will be fit in time to face Atletico Madrid next Thursday.
The Armenia international's return to action following a near month-long layoff lasted for 76 minutes before being taken off against former club Manchester United with a knee injury.
Mkhitaryan, who became the first ever player to score for and against United in the same Premier League season, will now be assessed early next week before a decision is made on whether he will travel to Madrid.
"We will see if Henrikh Mkhitaryan is available for Thursday," Wenger told BBC Sport. "I took him off because he had a bang on his knee."
Arsenal made eight changes for the 2-1 defeat to United ahead of Thursday's Europa League semi-final against Atletico, which is locked at 1-1 after the first leg.