Manchester United improved their 2015/16 record to two wins from two games with a 1-0 victory over Aston Villa on Friday.
The only goal of the match was scored by winger Adnan Januzaj.
However, Van Gaal would not guarantee that the Belgian international would stick around at Old Trafford and offered criticism for his performance.
“I was pleased with his goal. It was a wonderful goal, but you have to do more than just score a goal,” Van Gaal said, according to the Daily Star.
“He lost the ball too many times. That was less good. I didn’t substitute him because of that because I’d told him he would play 60 minutes.”
Januzaj was not expected to play for Man United, but Van Gaal surprisingly decided not to start Ashley Young.
Van Gaal will not commit to anything for Januzaj, but the 20-year-old has expressed his inclination to stay with Man United for the long haul.
“I hope to have more games and hopefully score more goals. Talk of me going out on loan was only rumours. I am happy here. Of course, I am going to fight for my place,” Januzaj said.
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The Dutch boss has already caught Man United fans by surprise with the choice to not make David de Gea the Red Devils’ starting goalkeeper.
Sergio Romero has stepped up in the net though, as he has come away with a clean sheet in each of his first two games after joining Man United on a free transfer deal.