Two months ago, shortly before Bethanie Mattek stepped onto Centre Court at Wimbledon to play Venus Williams, her business agent was on the telephone clinching a last-minute deal to earn her extra money.
For $1,000 apiece, Mattek, 21, of Miami, allowed a seamstress to sew two patches across the front of her tank top. One bore the name of a chocolate company, the other an Internet travel service.
Seen only fleetingly on television, the words were barely visible to courtside spectators at the All-England Lawn Tennis Club, but they made a strong impression on Mattek's bank account.
"Any little bit helps," she told ABC News.
The uncomfortable fact is that Mattek and hundreds of players on the lower rungs of the men's and women's top professional tennis tours scrape for extra dollars every day to survive financially.
To be sure, they are not as endangered financially as the players who inhabit the challengers and futures events, which are the tennis equivalent of the Nike Golf Tour. There, apprentices and veterans slug it out week after week for the right to do little more than share discount hotel rooms and worn-out cars as they travel from tournament to tournament.
From the outside, of course, professional tennis players -- even on the fringes of the sport -- seem to lead a glamorous and prosperous life: They jet from continent to continent. They often employ a coach, sometimes a trainer, and occasionally a business agent. They usually ride to and from the tournament grounds in chauffeured luxury automobiles (Lexus and Mercedes sponsor major tournaments).
But there is a dark side. First, consider -- and then disregard -- this most extreme example: In May, Katerina Bohmova, a 19-year-old Czech player, reportedly pleaded no contest to shoplifting $450 in clothes and jewelry from a Jacksonville, Fla., department store. In her sixth year as a touring pro, Bohmova has averaged barely $21,000 per year in prize money, according to Women's Tennis Association records.
Few of tennis' fringe competitors make the police blotter (we found only one). But many ride a financial rollercoaster that saps their energy and enthusiasm. Their love of tennis and desire to excel is often their only sustaining motivation.
Most are strapped for the money to pay ballooning airfares to take them to three continents and to buy the food, clothing and hotel shelter they need.
"For me, it's very tough," America's Mattek said. "Every once in awhile you get to play in a big stadium like this [Wimbledon's Centre Court]. It's wow, and cool. I mean, [to play] the rest of the tournaments, it's a struggle."
In the first six months of competition this year, Mattek won $62,002 in prize money. Her Wimbledon paycheck, for losing in the first round of singles, was $14,304, about $3,500 less than a men's player.
Would equal prize money for women make a significant difference?
"It definitely would help," she said. "It's really an expensive sport, especially for someone ranked around my ranking [103rd in the world]. You're paying for coaches, paying for your own [airline] flights, and meals and everything."
Mattek is the first to point out that Wimbledon treats its players better than most, extending generous per diem benefits for meals and free transportation within London.