Because from that time on I saw that I would never know entirely for sure whether a match I was playing would be my last. This understanding led me to only one conclusion: I’d have to play each one, and train for each one, as if it were my last. I had come close to tennis death; I had stared the end of my career in the face, and the experience, awful as it had been, had made me stronger mentally, given me the wisdom to see that life—any life—is a race against time.
