Serena Williams said defending her Internazionali d'Italia title was "not the end of the world", after easing into the third round in Rome.

The world number one dispatched of Anastasia Pavlyuchenkova 6-1 6-3 at the WTA Premier clay-court event, as she looks to add to her 66 career titles.

Usually ever competitive, the 19-time major winner claimed she was not desperate to win in the Italian capital as she continues her French Open preparation.

"I guess It's important [to defend this title] because obviously I want to win but it's not the end of the world," the American said.

"I'm here mostly to do the best that I can, try to improve and look forward to the upcoming several weeks."

Williams' likely opponent in the last 16 will be 13th seed and crowd favourite Sara Errani, with the top seed holding an 8-0 career head-to-head record against her.

Errani has only twice taken sets off Williams in those encounters, but most recently came closest to downing her in the Fed Cup World Group play-offs in April - only for Williams to edge the rubber.

"It would be great," Williams said of a potential re-match, with Errani to face Christina McHale in the second round on Wednesday.

"She [Errani] didn't get the chance to play her best last time we played.

"I played her in the Fed Cup it was an incredible match so I'll have my work cut out for me and I look forward to it."