Bale sustained the injury towards the end Real’s 3-1 win at Borussia Dortmund on Sept. 26 in which he had played a starring role to answer many of his critics in the Spanish media.
It was the eighth time he had damaged his left calf muscle since joining Real from Tottenham Hotspur in 2013 and his 10th calf problem since he moved to Spain.
Real originally said Bale’s fitness problems in Dortmund were related to cramp and allowed him to go on international duty with Wales.
Scans, however, soon revealed he had injured his calf and forced him out of Wales’s World Cup qualifiers against Georgia and Ireland.
Real later released a medical report stating Bale had a swollen calf but had not torn the muscle.
It did not give an estimated date for his return, and Zidane was unable to clarify the situation.
“I can’t say when he’ll be back, but he’s better, I can’t say if he’ll return in a week or 10 days, we’ll have to see,” Zidane told a news conference on Friday ahead of Real’s visit to Getafe in La Liga.
“He’s getting better every day. He had two problems, one in Dortmund when he only seemed a bit worn out, and then he had a different problem with his calf. Now we have to take it easy with him and be patient.”
Bale is ruled out of Saturday’s short trip to Getafe and unlikely to feature against former side Tottenham Hotspur in the Champions League on Tuesday, while he is also a doubt for the return game against Mauricio Pochettino’s side on Nov. 1.
Real are fifth in the Liga standings, seven points behind leaders Barcelona.
Bale, 28, has missed a third of Real’s games since he joined the club in a then world record move for 100 million euros ($118 million).
He had to watch most of last season’s Liga and Champions League winning double campaign from the sidelines due to a long lay off with an ankle injury and subsequent calf problems and later said he regretted rushing back too early after surgery on his ankle.
“Bale is the one who is most upset about this because he hates to be away from the team. I hope he returns quickly and plays like he did in Dortmund,” Zidane said.