Van Gaal: Lucky Man United must improve

Robin van Persie capitalised on defensive lapses from the home team in each half to help United chalk up a fifth consecutive victory despite a ragged display.

And Van Gaal, whose team now lie third in the table, refused to let his compatriot’s goals mask his concerns surrounding United’s general play.

He told Sky Sports: “We lost the ball too easily in the first half, I think. We didn’t have good positional play.

“The only chances that Southampton created were when we lost the ball. That was not good, despite our good result. We got a present from Southampton

“We needed confidence on the ball, which we didn’t have – I said that at half-time.

“I think Southampton played better than Manchester United but we were the lucky guys.

“I want them to show the confidence that we have shown on the training ground – this week we have trained fantastically.

“But I I didn’t see it on the matchday and that’s the most important hour. You have to show yourself on the matchday.”

The 19-year-old endured a torrid time under first-half pressure from Southampton and Van Gaal replaced him with midfielder Ander Herrera in the 39th minute.

Van Gaal conceded it was a tough decision to make but maintained he was looking out for McNair’s best interests.

He added: “He had not any confidence. He had already given three big chances away.

“It’s very disappointing for me and also for Paddy but I had to because as a manager I am responsible [for the] win.

“After the change we played a little bit better. Of course it is tough but it is also in his best interests.

“I have made a lot of [early] changes and all the boys can survive. It is only one moment in their lifetime.”