After nearly a year away from tennis, Williams had trouble with her serve but still managed to take a set from seventh-ranked Jelena Ostapenko.
ABU DHABI, United Arab Emirates — Serena Williams lost in her return to competitive tennis after giving birth, going down to the French Open champion Jelena Ostapenko at the Mubadala exhibition event here on Saturday.
Williams struggled with her serve. Ostapenko won, 6-2,3-6, and then, 10-5, in a supertiebreaker, but she still impressed to take a set off the seventh-ranked Ostapenko after nearly a year away from tennis.
Williams, 36, formerly ranked No. 1 in the world, had not played since she won the Australian Open, her 23rd Grand Slam singles title, 11 months ago. She was pregnant during that tournament and took time off to give birth to her first child, Alexis Olympia, in September. Her decision to play in the United Arab Emirates was taken by many people as a virtually confirmation that she would defend her title at Melbourne Park in January.
Williams, an American, broke Ostapenko, a Latvian, in the first game of her comeback, but her serving problems gave Ostapenko a way back into the match. They were the first women to compete in the Mubadala tournament, previously a male-only event.
