The Holland international's run of bad luck continued at the weekend...
The luckless Dutchman received a standing ovation as he entered the match after a ten-month injury lay-off and then reminded everyone of his talent with a goal.
That goal came with a cost though as Van Nistelrooy suffered another blow whilst beating the keeper with the strike late on in the 5-0 victory.
Tests on Monday morning have confirmed that the former Manchester United striker has a slight muscle tear at the back of his left leg and will be out of action for five or six weeks at least, according to AS.
On the flip side, Xabi Alonso returned to training with the first-team squad at Valdebebas having missed the weekend encounter after being injured during Champions League duty in midweek.
The midfield playmaker was able to run, but had to continue his recovery in the club gymnasium and will not be given the green light to play against Villarreal.
Lucas Brown, Goal.com