Serena Williams will face her sister Venus in the second round of the Internazionali d'Italia after they secured contrasting first-round victories on Monday.
Tenth seed Serena started her clay-court season with a commanding 6-4 6-2 over Rebecca Peterson at the Foro Italico.
The 23-time grand slam champion will do battle with her older sibling 21 years after their only other previous match in Rome, which Venus won at the quarter-final stage.
Venus, unseeded in the Eternal City, came through an almighty tussle with Elise Mertens 7-5 3-6 7-6 (7-4).
Madison Keys, Anett Kontaveit, Garbine Muguruza and Victoria Azarenka also made it through to the second round along with Amanda Anisimova, who will face newly-crowned Madrid Open champion Kiki Bertens.
SERENA LAYS DOWN A MARKER
Former world number one Serena overpowered Peterson in the opening match of what is only her fourth tournament of the year.
The 37-year-old, still eyeing a first title since becoming a mother in 2017, took only an hour and 16 minutes to get past the Swede in her first match in two months, having withdrawn from the Miami Open due to a left knee injury.
Serena, who will face Venus for a 31st time on the WTA Tour, said: "It felt good to be back in the match. It's been a while. I haven't played a ton of matches this year.
"Not my choice, just by force. I really, really actually desperately wanted to be on the tour and to be playing, but it hasn't been able to work out. It felt good to finally be back out. Hopefully I'll be able to keep it up."
VENUS STILL HAS THE STAYING POWER
Mertens would not go down without a fight as she refused to accept defeat against Venus.
The Belgian saved eight match points to force a decisive tie-break, with Venus unable to shake off an opponent 15 years younger than her.
Venus finally saw it out after three hours and two minutes on Grandstand Court, ending a contest that included 15 breaks of serve.
OSAKA TO FACE CIBULKOVA
Naomi Osaka will start her mission to retain world number one status and be top seed at the French Open with a clash against Dominika Cibulkova on Wednesday.
Osaka will achieve both of those goals if she makes it through to the quarter-finals this week, while Simona Halep must win the title to have any chance of replacing her.
Cibulkova saw off Aliaksandra Sasnovich 6-2 6-3 to avoid a first-round exit.