(CNN) She had been away from grand slams for 16 months, but Serena Williams said she felt like "a warrior princess" as she returned to winning ways at the French Open Tuesday.
The 36-year-old defeated Czech Kristyna Pliskova 7-6 (7-4) 6-4 in her first grand slam match since becoming a mom, but it was her eye-catching black catsuit that had tongues wagging.
Laughing as she made reference to the fictional nation in sub-Saharan Africa, which is home to superhero Black Panther from Marvel Comics, Williams told reporters: "I feel like a warrior in it, like a warrior princess, a queen from Wakanda maybe.
"It was comfortable to wear. I'm always living in a fantasy world. I always wanted to be a superhero, and it's kind of my way of being a superhero. I feel like a superhero when I wear it."
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The skintight outfit also serves a serious purpose, helping the 23-time grand slam champion's blood circulation after a difficult childbirth.
In an opinion piece for CNN in February, the former world No.1 described how she almost died while giving birth to her daughter, Olympia.
Williams, who gave birth in September, added: "I had a lot of problems with my blood clots. God, I don't know how many I have had in the past 12 months. So there is definitely a little functionality to it.
"I have been wearing pants a lot when I play so I can keep the blood circulation going."
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Though she is the most successful female player of the open era, with a ranking of 451 in the world she is not seeded in Roland Garros.
Hitting 13 aces and lifting her game when trailing in a first-set tiebreak, the American overcame a player 381 places above her in the rankings in an hour and 45 minutes. Australian Ashleigh Barty awaits her in the second round.
In an Instagram post after her victory -- her first match on clay since the 2016 French Open final -- Williams wrote: "Catsuit anyone? For all the moms out there who had a tough recovery from pregnancy—here you go. If I can do it, so can you. Love you all!!"
Williams, who won the 2017 Australian Open in the early stages of pregnancy. told reporters she felt she was "on the right track."
"I have been putting a lot of work in on the court, off the court, on the court, on the court, off the court, that's kind of been my life," said Williams, who had arrived at the French Open on a two-match losing skid and with no warmup matches on clay.
"I have been really enjoying it. Hopefully the results continue to show."
Williams' tiebreak against fellow big server Pliskova -- twin sister of former No. 1 Karolina Pliskova, who beat Serena at the 2016 US Open -- felt decisive.
The world No. 70 saved the lone break point of the first on Philippe-Chatrier court, a set point, at 5-6 with an ace. As a result, the Czech held the momentum going into the tiebreak and duly raced to a 3-0 advantage.
A combination of factors changed the complexion. Williams refused to donate any errors while Pliskova blinked, perhaps realizing how close she was to taking a set off the tennis great.
Pliskova regrouped for 2-0 in the second set but didn't recover when broken from 40-15 in the ensuing game, although Williams needed to save a trio of break points to confirm her passage into the second round.
Williams' longtime rival Maria Sharapova endured a longer absence from Roland Garros after a drug suspension -- and famously not receiving a wildcard last year -- but the Russian also emerged victorious in the first round.
Her path was ultimately trickier, with the Russian needing to overturn a break deficit in the third set against 133rd-ranked qualifier Richel Hogenkamp for a 6-14-6 6-3 win. It initially looked like the 31-year-old was destined for victory in an hour.
Former French Open champion Sharapova, in Williams' quarter of the draw, said: "Great to be in this draw. Great to be back on a court that I have had great success at.
"I have always loved playing here. From a young age, it was a grand slam that was very difficult for me to do well at physically, mentally. I overcame that."
Meanwhile, such is his pedigree on clay that Rafael Nadal hardly experiences any drama at the French Open.
But the record 10-time champion was forced to save a quartet of set points in a thrilling tiebreak prior to putting away the flashy Italian, Simone Bolelli, 6-4 6-3 7-6 (11-9) in the completion of their opener.
The victory over the 32-year-old improved the 31-year-old's record at Roland Garros to 80-2
The overwhelming favorite in the men's draw, Nadal said complacency would not be an issue going forward and never has been.
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"If you get complacent or too confident with yourself, for sure that's not gonna happen," said Nadal. "I was able to do all this result because I respect the sport, I respect every opponent, and I respect the competition every day.
"That's the reason I have success, is because I go every day on court knowing that I can win, that I can lose."