The forward has undergone surgery after a major car crash involving his Ferrari.
Lopetegui has confirmed Antonio broke his leg in the accident, stating: "The most important thing is that he's alive, he's good. He broke his femur, but he's going to recover for sure.
"He's going to need time. It's about time. Now it's about time but the good news is that he has time because when you see the car was terrible, the accident, that's why we are happy.
"Because in the end, despite the fact we are unhappy because we lost one very important player for us, we are happy because he's going to be ready.
"Now he's strong, he's recovered himself in the next month for sure and he's going to be ready to be a player.
"The first thing is to be a man and then to be a player."
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