The 29-yer-old Bale, Real's record signing, sustained the injury during Madrid's 2-2 draw at Villarreal in La Liga on Thursday and asked to be substituted at halftime.
Real's statement on their website https://www.realmadrid.com/en/news/2019/01/bale-medical-report said Bale had a grade one injury but did not give details on when they expected him to return to action, although reports in the Spanish media said he would be out for between two and four weeks.
The injury definitely rules Bale out of Madrid's Liga games against Real Sociedad and Real Betis in addition to the two Copa del Rey last-16 games against Leganes this month.
He also risks missing a crunch match on Jan. 19 at home to high-flying Sevilla, who are two points above Real in the table.
Bale has enjoyed better fortune with injuries than in previous campaigns since joining Real from Tottenham Hotspur for a then world record fee of 100 million euros (89.5 million pounds).
He has been widely criticised in the Spanish media for his meagre goal tally, though, with four strikes in 15 Liga games, and for failing to fill the void left in Madrid's attack by all-time top scorer Cristiano Ronaldo's departure to Juventus.
(Reporting by Richard Martin; Editing by Ken Ferris)
