There has been no timeline mentioned yet on his return, however, fans can be assured that they will be seeing a lot more of Isco rather than Bale.
Bale "felt some discomfort in his left leg" after training on Thursday, and tests on Friday revealed "a strain to the middle third of the adductor longus muscle in his left leg", the defending European club champion said.
He is likely to be available for the Madrid derby against Atletico after the worldwide break. "His recovery will continue to be assessed".
He had returned to training last week and was named in Wales' squad for friendlies against France and Panama.
Bale stands to miss both the Atletico match and a Champions League game against APOEL.
Just 15 months on from carrying his country to the semi-finals of Euro 2016, Bale also had to watch on in agony from the stands as Wales' attempts to qualify for a first World Cup since 1958 fell short last month.
Isco admits that Real Madrid teammate Gareth Bale "is having a hard time", having been ruled out of action for a further month or so.