Serena powers past No. 1-bound Osaka, Halep retires hurt

Serena Williams won the rematch Friday, dominating Naomi Osaka 6-3, 6-4 to ensure the Japanese star won't leave Toronto with a title to go with her number one world ranking.

Williams fired 12 aces and didn't face a break point as she beat Osaka for the first time in three meetings -- avenging her shock loss in last year's controversial US Open final in which the American star was docked a point and a game after losing her temper when warned about coaching.

There was no such drama in Toronto, where Williams broke Osaka for a 5-3 lead in the first and closed out the opening set with a service winner. She broke again for a 2-1 lead in the second and never looked like surrendering the advantage.

Even a run-in with the net cord -- as she raced forward trying to run down a drop shot -- didn't faze her.

"It hurt, but it wasn't the end of the world," Williams said.

The American's lone wobble came in the final game. After a pair of aces gave her a triple match point, Williams offered up a ...