Serena blazes into second round at French Open

Serena Williams declared she was "not a cold-weather person" but her game still caught fire as she demolished Slovakian Magdalena Rybarikova 6-2 6-0 to start the defence of her French Open title on Tuesday.

The American, who owns 21 grand slam singles titles, will next face either Brazilian Teliana Pereira or Czech Kristyna Pliskova.

Rybarikova hung on until 2-2 in the first set before Williams went into overdrive to win 10 games in a row.

She wrapped it up on her first match point when Rybarikova sent a crosscourt backhand into the net on a cold day at Roland Garros.

"I'm not a cold-weather person. It's been really tough," Williams told reporters after her match was played out in 13 degrees Celsius.

"Today it was warmer... a couple matches before (mine), but by the time I got out there, it was just really cold.

"I don't like playing in cold weather. But everything felt pretty good, so it was okay."

Williams delayed the start of her claycourt season as she skipped the Madrid Open because of illness, kicking it off earlier this month in Rome, where she won the title without dropping a set.