Anthony Martial will need a scan on his hip after picking up a knock in Manchester United's Europa League draw with AC Milan.
The striker was replaced by Amad at half-time of United's 1-1 draw in the first leg of the last-16 tie, with the 18-year-old replacement scoring five minutes after coming on.
Martial had limped down the tunnel with the game goalless at the break and he didn't reappear for the second half, adding to United's growing injury list.
Ole Gunnar Solskjaer confirmed it was an injury the Frenchman picked up in the first half and that he would need to be assessed.
“Anthony got a whack on his hip so there’s another forward we need to scan and look at," he said. “Unfortunately, he got a whack on his hip quite early in the first half so he couldn't go on."
United were already without Marcus Rashford and Edinson Cavani for the Old Trafford clash with Milan, leaving only Amad and 17-year-old Shola Shoretire as attacking substitutes.
With United clinging on to a 1-0 lead Luke Shaw finished the game in a left midfield role and Simon Kjaer scored an injury-time equaliser for the Rossoneri.
Solskjaer expects Martial and Cavani to miss the Premier League game with West Ham United on Sunday, but he said before Thursday's match that "hopefully" Rashford would be available.
