Check & Mate (by Ali Hazelwood)

More college-age than truly young adult (I've heard this called "new adult") and a good read about a chess rivalry. This is one I kept checking out and letting lapse because the cover is juvenile and just not appealing.  But the book is much more sophisticated than the cover would suggest.

Mallory is a chess prodigy who quit the sport after some unspecified trauma with her deceased father. She now takes care of her mother (who is chronically ill) and her two younger sisters by working under the table as a car mechanic.  Until she is drafted to play in a chess competition and beats the #1 player in the world, who is of course a hot chess prodigy.

I enjoyed: the dialogue, the relationship of the sisters, the bisexual and sex-positive representation. Less effective: I felt the "best friend" owed her an apology at the end and that never got resolved, and I can see how the ending might feel a bit unsatisfying.  But overall I enjoyed it.