Wayne Rooney may have had the hump with Louis van Gaal but the England international was still a key figure in Manchester United's 1-0 Premier League win at Norwich City.

The vastly-experienced Dutchman revealed Rooney was less than impressed at being pushed further forward following a pre-match injury scare for Anthony Martial.

The French international was a late call-off, forcing van Gaal into a positional change for England's record goalscorer, but Rooney provided the assist for Juan Mata's winner.

'I don't think he was very happy with me that I decided to put him in the striker's position, but he could imagine also (why he had to play there). He can understand,' said van Gaal. '(Adnan) Januzaj played his first half for the second team recently and I could not put him in the line-up as a striker so Wayne has to do that. And he did it very well because he gave a fantastic assist to Juan Mata. Anthony felt something and I am a manager who does not take risks. He had a tight muscle but we have to wait and see the reaction.'

The United chief was also forced to replace Matteo Darmian who damaged his ankle inside the first 20 minutes, while teenage sensation Marcus Rashford and Daley Blind were both rested.

'Matteo had a kick on the ankle and he is walking in a brace but we have to wait,' said van Gaal. 'I have seen this situation many times this season but we have also seen that this team can handle that. I cannot give everybody a rest and that is the problem. You have to make these decisions before the game and not after it. After the game, you can decide what you want but it doesn't count anymore.

'I thought Daley and Marcus needed a rest because they have played a lot of matches, nearly every match. Rashford is a youngster and he's played the last 10 games so it's not easy for him and he needs that rest.

'I wanted to give him this game off. You see in a game that he's not doing things any more that you saw him doing in his first match or his second match.'

United's new-look line-up still had too much for Norwich to keep alive their outside hopes of finishing in the top four and qualifying for the Champions League next season.

'We are still in the race,' said van Gaal. 'Yes, it's so important that we are still in business and we keep in business by keeping the pressure on our competitors. It's so important. I'm very happy. It's not easy as Norwich is fighting against relegation and we have to win because we lost two points against Leicester. Now we are still in the race.

'We did our job. Fantastic, I think. When you see the second-half, we deserved to win.

'The weather makes a huge difference. Last week, it was more or less cold and five degrees, now it was 25 degrees. It's hot on the players' faces and they were very tired. You can see my players and Norwich players it is a blow for them.

'I said to the boys, 'We have to win, there is no excuse,' but they were fighting and pressing and running on each ball. There is always more pressure on us but in the second-half we kept the ball better and easier and that is why we had more than one chance.'