1 Serena Williams calls her “the future of American tennis.”

She made that proclamation at last summer’s U.S. Open—before beating Townsend, who now ranks No. 94 in the world, in straight sets. “They’re genuine friends,” says Kamau Murray, Townsend’s coach. “They respect each other because they both struggled early in their careers.”

2 She’s helping bring tennis to the South Side.

Townsend, who grew up in Chatham and Englewood (where she lives when she isn’t training in Washington, D.C., or Boca Raton), successfully lobbied the Chicago Housing Authority to build a $9.8 million tennis facility in Bronzeville. “Tennis is a very white sport,” she told the Tribune.

3 Her weight has been an issue.

The U.S. Tennis Association created a stir in 2012 when it asked Townsend, then 16, to sit out the junior U.S. Open unless she slimmed down. (The 5-foot-6 Townsend still plays at the same weight, 170 pounds.) That roundly criticized stance led her to split from USTA coaches.

4 She’s a throwback.

Her serve-and-volley style is rare in modern tennis. “She’s aggressive,” Murray says. “She tries to go to the net and finish.”

5 She’s killer on clay.

At the 2014 French Open, her first Grand Slam, the former top-ranked junior scored two upsets to advance to the third round. She was the youngest American to do so in five years.