For the First Time, 3 Moms, Including Serena Williams, Are in the US Open Quarterfinals

Pironkova, 32, is currently playing her first tournament in three years since her 2017 Wimbledon appearance, NBC Sports reports. She was a semifinalist at Wimbledon in 2010, and she gave birth in 2018 to a son named Alexander, returning to tennis eight months ago.

"Obviously, you become a different person," Pironkova said of motherhood, according to NBC Sports. "You don't focus on yourself that much anymore." She added that she's a lot more organized, has increased mental endurance, and knows her body better.