It's understood that he started as an actor, learning his craft as an unknown. What he did next was extremely canny, and something somewhat outside the realms of possibility for writers, producers, or actors in this modern world.
The life of a squash player is one that demands focus and huge amounts of dedication and it is quite difficult to really think of anything else. Being the best you can requires full throttle effort. Which is probably why many of us get to 35 and don't have a clue in hell what to do next.