Yikes - Serena says she isn't playing strong yet

NEW YORK (AFP) - Serena Williams rampaged through her first four matches at the United States (US) Open, dropping only 12 games along the way, but she says she has not even started out strongly on the Flushing Meadows hardcourts.

Three-time winner Williams, a 14-time Grand Slam champion, cruised into the quarter-finals on Monday by crushing 82nd-ranked Andrea Hlavackova 6-0, 6-0 in 57 minutes, firing eight aces and 31 winners.

The reigning Olympic and Wimbledon champion has dominated women's tennis over the past two months and rules nowhere more than in New York, where her 62 career match triumphs are the most of any active player.

"I honestly don't think I started out strong in the tournament," Williams said.