Manchester United boss Jose Mourinho had a pop at his medical staff after their stalemate at Sevilla.

Ander Herrera pulled up with a serious hamstring injury during the Champions League clash.

The Spaniard has missed United's last three matches with a hamstring injury, but returned to the starting XI in Seville.

"I think it is a bad injury," explained Mourinho. "He had a small injury that stopped him for the last couple of matches but the medical team said he was 100 per cent ready for the last Saturday.

"We didn't play him to give more work and more protection, but it looks like he wasn't fully fit.

"The medical department made him fully fit. He trained and he looked fit. The way he was playing he showed that intensity that is only possible when you're fit.

"He was pressing really high, we were not giving one inch to them. Then the backheel created the contraction in the muscular error and now we have proof he was not 100 per cent fit."