so you think Borg retired too early ?..think again.
Borg made his debut at the stockholm open starting nov 1st 1971
and fell off the tour at the tokyo open that was end of oct 1981..
he was age 15yrs 4months when he started, and played 715 singles matches in a career lasting almost exactly 10yrs to the day..
he also played freak knows how many exhibition matches/tourneys such as the suntory cup etc (beat mcenroe in 1983 there)..also i know he played a couple of tournys on the main tour in 82 like monte carlo until ending in july 84 in germany, but we all know really he stepped off the tour in 1981.
so thats 715 matches in 10yrs, plus the fact that the tour gave the players far less help off court than they get nowadays...then i say maybe he played alot at a high level for a long time rather than quitting early.