Roger Federer blames a bathroom mishap while on parental duty for the knee injury that forced him to have surgery for the first time.
Speaking Thursday on the eve of his first match since the Feb. 3 operation, Federer said he hurt himself while preparing a bath for his twin daughters.
He turned and heard a click in his left knee. Soon his knee was swollen, and a few days later he had arthroscopic surgery for torn cartilage.
The 34-year-old Swiss great is to return Friday when he plays Juan Martin del Potro at the Miami Open.
Federer has been a model of durability throughout his career. He's playing Key Biscayne for the 16th time, although he did skip the tournament last year.