Serena Williams is through to the second round of the BNP Paribas Open in Indian Wells, Californian, beating Zarina Diyas 7-5 6-3.
Diyas is ranked 53rd in the world.
The match was the first victory for the former world number one, since she returned to competitive tennis after giving birth to her baby, Alexis Olympia in September.
Serena, 36, had played at an exhibition game and also played doubles for United Ststes in the Fed Cup. She was beaten in all the matches.
All eyes were thus on her as to whether she would survive another test in California. She did in the nervy first round.
She will meet Kiki Bertens on Saturday in the second round.
Williams entered the court Thursday night to a loud ovation, with many in the half full stadium standing and applauding as she came out of the tunnel for just her third appearance in Indian Wells in the last 17 years.
After that it was a matter of gradually asserting herself by taking control of the rallies, and she got the first break of serve in the 11th game of the first set and secured the set in the next game on her third set point.
The 36-year-old American is the star attraction in Indian Wells, but behind her popularity this year was the mystery surrounding her match fitness and ball-striking ability.
The 23-time Grand Slam winner answered some of those questions Thursday by blasting four aces and winning 63 percent of her first-serve points against a tough opponent who claimed her first WTA title last year in Tokyo.
Williams also won an whopping 64 percent of her second serves and broke Diyas, ranked 53rd in the world, five times in the 92 minute match.
She had four double faults, but her impressive second serve win ratio was evidence of a game plan that included being aggressive and not sitting back and allowing Kazakhstan’s Diyas to dictate the pace of play.
A win over Bertens on Saturday could see her face older sister Venus in the third round.
Venus, who is seeded eighth, enjoyed a first round bye and will play Romania’s Sorana Cirstea in her opening match.
Indian Wells features a star-studded women’s field in a tournament that looks wide open for the taking by any of the top 10 seeds, led by world number one Simona Halep.