Louis van Gaal wants consistency from Man United debutant Marcus Rashford

MANCHESTER -- Manchester United manager Louis van Gaal challenged Marcus Rashford to deliver consistently after the striker enjoyed a dream first-team debut at Old Trafford.

The 18-year-old scored twice to help United secure a 5-1 win against FC Midtjylland on Thursday, earning a 6-3 triumph on aggregate and progression to the last 16 of the Europa League.

Manchester-born Rashford was only thrown into action just before kick-off when Anthony Martial withdrew with a hamstring concern, while left-back Joe Riley was also handed his first start.

Van Gaal said that Martial's injury is "not heavy."

When asked about Rashford in his postmatch news conference on Thursday, Van Gaal said: "That's fantastic for him, but you have to be consistent. We are looking for consistent strikers. There are not so many on this Earth, but he made a great performance.

"I didn't have another option so it was easy. He was there on the bench because he was the natural sub for Martial. I put Riley in there because he is playing left-back in the second team and I have seen him play well.

"The first match [for young players], they always play good. That's not a problem. It's the second or third game that normally gives them problems."

The United manager also praised Memphis Depay for his impressive display.

"I am very happy for Memphis," he said. "Maybe it's a turning point for him, you never know. I hope with all my heart."

Midtjylland manager Jess Thorup was impressed by United's young players, hailing Rashford's display.

He said: "He played an almost perfect game. We know about the young boys they have. That's why they are at Manchester United -- because they have 'something.' That's why they are playing here."