Serena Williams shook off the rust after 18 months away from the hardcourts to post a 6-3, 6-4 opening win on Monday at the WTA Toronto Masters.
Williams survived a 25-minute eighth game of the second set to finally overcome lucky loser from qualifying Nuria Parrizas Diaz, ranked 57th.
The 40-year-old whose only other outing this season was a first-round Wimbledon loss, last won a match in May of last year at Roland Garros.
She last competed on cement at the 2021 Australian Open, played in early February.
Williams is on court in Canada for the 10th time in her career, the first of her three titles in the country came in 2001 and her last in 2013.
The American advanced to the second round with seven aces, salvaging seven of eight break points.
Williams was joined as a winner by fellow former Grand Slam champion Simona Halep.
The Romanian won the first seven games as she dominated with the loss of only two games against qualifier Donna Vekic in barely an hour.