Martina Hingis, shown in a recent match against Boston, won both her singles and women’s doubles matches on Monday night to lead the Washington Kastles to a 23-13 World Team Tennis victory over the Philadelphia Freedoms. (Nick Wass/Associated Press)

Martina Hingis administered a few lessons to a former pupil Monday at Kastles Stadium, helping the Washington Kastles to a 23-13 victory over the Philadelphia Freedoms in World Team Tennis.

After the Kastles started out with a 5-3 mixed doubles win, Hingis squared off against Sachia Vickery — whom she used to coach at the Mouratoglou Academy in France — in women’s singles.

Vickery, 18, playing her first set in the league, showed some early nerves with numerous unforced errors and double faults. Her former coach cruised to a 5-0 victory.

“Team Tennis is tough, getting thrown in the first time,” Hingis said of her pupil. “You feel like a fish out of water.”

After the Kastles’ Frederik Nielsen and Bobby Reynolds fell, 5-3, in men’s doubles, Vickery paired with Liezel Huber to face Hingis and Anastasia Rodionova. Vickery fared better, winning both games she served and engaging Hingis in several backhand battles.

Huber, on the other hand, struggled with a head injury suffered when she was hit with a ball in warmups. As the set wore on, she appeared dazed and was eventually unable to continue. That left Vickery to take on Hingis and Rodionova one on two.

With Serena Williams cheering from the stands — and the crowd cheering for Serena to join Vickery — the rookie won a point, though the Kastles won the set, 5-3.

Reynolds took down power-server Sam Groth, 5-2, in men’s singles to seal the victory. The Kastles (10-2), who have clinched hosting the Eastern Conference finals Thursday, will play at New York on Tuesday before concluding the regular season Wednesday at home against Boston.