Angel di Maria had long since departed the stage by the time Wayne Rooney struck twice to challenge Louis van Gaal’s claims that Manchester United lack a 20-goal striker.

Di Maria was hooked at half-time, paying the price for another poor performance. It was a humiliating exit for United’s record £59.7million signing.

Van Gaal insists that Di Maria just needs time to adapt to the Premier League, but there are concerns over the manner in which the Argentina star has faded after a bright start in English football. His contribution against Sunderland was negligible for a player of his pedigree.

Former Real Madrid midfielder Angel di Maria is on a poor run of form for Manchester United

It has raised questions over whether Di Maria and his family have settled in this country, particularly after raiders targeted their Cheshire home last month.

However, Rooney has no doubts that the former Real Madrid man has what it takes to be a success in the Premier League.

‘Of course he has,’ said the United captain. ‘Today was one of those days that every footballer has.

Di Maria, in action against Sunderland, was taken off before the second half at Old Trafford on Saturday

Manchester United captain Wayne Rooney (right) believes Di Maria will rediscover his best form soon

‘He is a great player, he has shown that and you don’t lose your talent overnight. Hopefully he will get back to his best and start giving some great performances for us.

‘He has got a lot of experience and I think he will figure it out. We all have to do that sometimes.

‘There is nothing worse than when everyone keeps going on at you. You have to come to it in your own way and I’m sure he will be a big player for us between now and the end of the season.’

After hearing his manager lament the need for a striker capable of scoring 20 goals a season, despite playing him in midfield for a significant part of the campaign, Rooney gave Van Gaal a timely reminder of what he does best.

England and Manchester United forward Rooney heads in their second at Old Trafford on Saturday

Rooney jumps into the air in celebration as the striker scored twice to secure the three points

The England striker’s two goals took his total to 11 and also made him the first player in Premier League history to hit double figures in 11 successive seasons.

‘I was obviously pleased that the manager played me up front and delighted to get the two goals,’ said Rooney.

‘I’ve played there throughout my career so obviously I know how to play up front. I’m ready to play there if and when he wants me to do it.

‘Everyone knows I’ve played midfield for the majority of the season but my record shows that I score goals so I’m not worried about that at all.’

Rooney scored his first from the penalty spot after Wes Brown was controversially sent off for fouling Radamel Falcao when replays clearly showed that it was John O’Shea who made contact with the Colombian.

However, if referee Roger East maintains his stance that he saw Brown foul Falcao in the act of shooting and sent off the right man, it is understood that the FA will be powerless to overturn Brown’s red card.