The financial pressures have raised concerns about match fixing. Several players at the Futures level, largely based in Europe, have been sanctioned by the Tennis Integrity Unit.

Aubone said he had never been approached and had no evidence of anyone else being approached.

“I have no proof that anything is going on, but I just think there is way too much talk about it,” he said. “I’ve received hate messages, which I imagine were from bettors, because I have no idea who they are, and they are pretty upset I lost a match.”

Aubone said he could understand low-level players’ temptation.

“I mean I’ve thought about: What if I was in that position? What if I was approached?” he said. “Someone said: ‘Here’s 100 grand. One match or not even one match. One set. You can still win the match.’ My year is set; two years if I want to continue traveling this way. You’d be an idiot to not at least think about it. But you’d be more of an idiot to take that route.”

A former Florida State player, Aubone said he gave up a nascent finance career at Morgan Stanley in 2012 to return to the pro tour. He is now ranked 570th. He spends an estimated $35,000 a year on tennis and travel expenses.

“My bosses thought I was crazy,” he said. “Obviously I love tennis, but for me it’s just for the possibility of playing in the U.S. Open again. In 2008, I got a wild card from the U.S.T.A. and was fortunate to win a round in men’s qualifying, and that feeling, that atmosphere, being around everybody there was priceless, uplifting, just energy.”