The Mexico striker scored in United’s 3-1 Community Shield victory over Chelsea at Wembley on Sunday.
“He has been looking good for the last 10 days since he joined us in the United States,” said Van der Sar.
“How he scored does not really matter – the most important thing was for him to get on the scoresheet and for the fans to see a very talented player.
“He is a big prospect. More players are emerging and together with the experienced ones we have to try and bring something back.
“However, we don’t just need the strikers to score. It is the midfielders and wingers who need to do their bit as well.
“(Antonio) Valencia scored and crossed for the second one. He is looking well.
“That is important. You need goals from lots of different places.”
