Manchester United boss Louis van Gaal hooked Angel di Maria at halftime of their 2-0 win over Sunderland. Van Gaal said Di Maria was removed because of his poor performance and not due to injury.

"I want to win as a manager and I have to observe and analyse and I have to take the steps that are necessary," Van Gaal said when asked about substituting the most expensive player in British football.

"I always thought in theory that I could change Angel for Adnan Januzaj and then we were in the second half better.

"We have to give Angel more time to adapt to the Premier League; it's not so easy with the high tempo. I want to give him time, it's also not easy to change a player of his quality, but I have to make these decisions."