"A Handful of Summers" is probably the finest book written about tennis in the world before the Open era.
No, check that...it IS the finest book about what it meant to be a tennis bum, especially for readers who were born after, oh, say 1965, for whom "tennis bum" is an oxymoron. I mean, come on, the 100th player on the INDESIT board has earned $117,000 this year. The word bum does not apply.
I have not read "Too Soon to Panic", but Forbes' writing in "Summers" is so good that I'll go out on a limb and recommend "Panic", too. You don't have to understand what the phrase "tennis bum" meant to appreciate the word "elegiac", and that's Forbes' memoirs to a t, along with another word: humorous.