The Netherlands international was a key part of Van Gaal’s Oranje side but the talismanic Roma star missed the World Cup due to a knee injury which he suffered in March.
It is not easy to say how he comes back from injury, but we will wait and see
Louis van Gaal
Strootman has been heavily linked with a move to United since Van Gaal’s appointment as the Red Devils bid to strengthen their midfield.
The 62-year-old United manager has already snapped up Ander Herrera and has been continuously linked with Juventus star Arturo Vidal.
However, Van Gaal is still monitoring the 24-year-old ahead of United’s pre-season friendly against Roma on Saturday evening.
“Strootman I can judge, but he is injured for more than six months,” said Van Gaal.
“We have to wait and see how he comes back. It is not easy to say how he comes back from injury, but we will wait and see.”
Strootman, who joined Roma from PSV Eindhoven in 2013, scored five goals and made six assists in 25 Serie A appearances last season.
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