Manchester United manager Louis van Gaal has eased concerns over Anthony Martial's hamstring injury, but was unable to confirm whether the forward will be ready for the Premier League clash with Arsenal on Sunday.

Martial, 20, suffered the injury in his final warm-up ahead of his side's Europa League second leg clash with Midtjylland at Old Trafford. His absence was cushioned by a sensational debut from his replacement Marcus Rashford, who struck twice in the second half, but the Frenchman's injury will be a concern given United's already lengthy injury list.

Speaking to BT Sport after the 5-1 victory that secured United's place in the last 16, van Gaal praised Martial's decision to not risk aggravating the problem further by playing.

"This is a muscle injury. I think he is smart, he is wise to step out because it was not a rupture or something like that, he had a tight hamstring, so I don't think it is very heavy."

The sight of Martial limping off before the match started was met with horror by United fans with Wayne Rooney and Will Keane already sidelined. But 18-year-old Rashford filled the void with a hugely impressive debut, scoring twice within 12 minutes in the second half, easing the tension around Old Trafford with the game poised at 1-1 at half-time.

The hugely impressive Memphis Depay won a penalty for his side with three minutes remaining after his curling effort was blocked by the hand of Kian Hansen. After Juan Mata missed from the spot in the first-half, his countryman Ander Herrera took over duties and hammered into the top corner from 12 yards out. Depay sealed a thrilling second half with a well-deserved effort, finding the bottom corner from the edge of the box.