Manchester United boss Louis van Gaal is worried about Luke Shaw's fitness struggles.

Shaw, a £28 million summer signing from Southampton, has endured an injury-ravaged campaign at Old Trafford and Van Gaal admits he is concerned by the player's inability to build a sustained run in the team.

"You are right," Van Gaal said, when asked about concerns over Shaw's injuries. "I have put in the same question as you did.

"It's a very interesting question, but I don't speak about our conversations with players; I'm sorry."

Van Gaal insists, however, that the fitness concerns he raised over Shaw during the summer are no longer an issue.

"It was a long time ago," Van Gaal said. "That was the beginning of our relationship and collaboration. That has passed."