PARIS -- Serena Williams has won her first Grand Slam match as a mother -- and first match at a major in 16 months -- with a 7-6 (4), 6-4 triumph over Kristyna Pliskova at the French Open on Tuesday.
Williams, wearing an all-black bodysuit with a red waistband, defeated the hard-serving Pliskova, from the Czech Republic, to reach the second round.
"I'm just happy to win a match here," Williams told the crowd in Court Philippe Chatrier. "I'm just happy to take it a day at a time."
For all that has changed during her time away from Grand Slam tennis, so much seemed familiar on Tuesday. The fashion statement. The cries of "Come on!" The big serves that provided 13 aces. The return game that produced three consecutive breaks of serve.
Something that was new, however: the title of working mother.
"Well, my priority is Olympia. No matter what, that's my priority," Williams said. "I have given tennis so much, and tennis has actually given me a lot, and I couldn't be more grateful. She's my priority, and I work everything around her."
After falling behind 3-0 in the first-set tiebreaker, Williams reeled off six points in a row. After falling behind 2-0 in the second set, Williams came up with a trio of service breaks.
"I'm definitely here to compete and do the best that I can do, obviously. I'm not putting any pressure on myself as I normally do," Williams began, before continuing after a pause and a laugh. "... I think deep down, we all know the answer to that."
A three-time champion at Roland Garros, Williams, 36, had not played a competitive match on clay this season ahead of her first-round match against Pliskova, who had 15 aces.
Pliskova, a lefty whose twin sister upset Williams in the 2016 US Open semifinals, actually hit more aces, 15. That's the most anyone has hit against Williams since at least 2008, according to the WTA.
Indeed, Williams appeared to have trouble reading Pliskova's serves early on. There were other blips, of the sort to be expected from someone who hasn't played lately. Williams double-faulted seven times. She had nearly as many unforced errors, 25, as winners, 29.
In the final game, Williams' right foot gave way as she sprinted toward the net and she landed on her backside. At least she was able to laugh at that as she went to the sideline to towel off. A spectator yelled: "That's all right, Serena! You still look great!"
Williams next will face Australian Ashleigh Barty, who is the 17th seed.
"She's a genuine champion," Barty said. "What she's done to be able to get back ... is a pretty amazing thing."
Two-time Grand Slam winner Garbine Muguruza is back to her winning ways in Paris after beating 2009 French Open champion Svetlana Kuznetsova 7-6 (0), 6-2 to reach the second round.
After beating Williams in the 2016 final, Muguruza's title defense ended in the fourth round last year.
Now ranked 43rd, the 32-year-old Kuznetsova was making her 16th consecutive appearance in the main draw in Paris.
Two-time French Open champion Maria Sharapova of Russia was pushed to three sets in her return to this event following a two-year absence. She was given a tough challenge by Dutch qualifier Richel Hogenkamp, but Sharapova eventually prevailed 6-1, 4-6, 6-3.
It was Sharapova's first win at the French Open since 2015. She served a drug ban in 2016 and was not granted a wild card last year.
Sharapova led 6-1, 4-3 but lost the next six games as Hogenkamp led 3-0 in the decider. Sharapova managed to turn things around, and Hogenkamp angrily tossed her racket at the red clay after Sharapova resisted pressure on her serve in the sixth game, saving two break points.
With Tuesday's matches delayed because of rain earlier in the day, No. 1-ranked Simona Halep had her first-round match postponed until Wednesday. The two-time finalist was to have faced American Alison Riske in the final match on Court Philippe Chatrier.
There are no artificial lights at Roland Garros and organizers figured there might not be enough sunlight to get the women's match started, let alone finished, on Tuesday.
The Associated Press contributed to this report.