Flushing Meadows, NY -- (Sports Network) - Defending champion Serena Williams dismissed 22nd-seeded Daniela Hantuchova in straight sets Sunday to advance to the quarterfinals, while her sister Venus was sent packing with a loss to wild card Kim Clijsters at the U.S. Open.

Second-seeded Serena overpowered her Slovakian opponent, winning 10 straight games to close out the match at Arthur Ashe Stadium, 6-2, 6-0. The American superstar belted 27 winners to her opponent's nine and also recorded eight aces in the victory that took 64 minutes.

"I traditionally play really well in my fourth-round matches," Serena said. "I just want to keep this level and just stay focused and play well my next match."

Serena, who already has two Grand Slam championships this year, having captured titles at the Australian Open and Wimbledon, is a three-time winner at Flushing Meadows.

Next up for Serena will be 10th-seeded Flavia Pennetta of Italy. Pennetta won an 81-minute second set to even her match against seventh-seeded Russian Vera Zvonareva, then swept through the third set in 33 minutes to complete the 3-6, 7-6 (8-6), 6-0 victory.

Former world No. 1 Clijsters of Belgium snuck past third-seeded Venus, 6-0, 0-6, 6-4, in 1 hour, 42 minutes to mark her spot in the round of eight.

The 2005 U.S. Open champion Clijsters, who took two years off to get married and have a child, took control of the match early. Clijsters didn't drop a game in the first set, which was over in just 27 minutes.

Venus, the 2000 and 2001 U.S. Open champion, fired right back with an impressive second set of her own. This time, it was Venus who didn't drop a game in a 23-minute set.

Clijsters held a 5-4 edge in the third set, but found herself down 40-15 in the 10th game. Clijsters fought back and had a match point after Venus fired a backhand return into the net. She finished the match off with an ace.

This was Venus' earliest exit at the U.S. Open since 2004.

"I know today that Venus wasn't playing her best tennis," Clijsters said. "In that sense it's hard to kind of compare anything in today's match. But there's a lot of other things personally that I'm taking out of this match. That's just the mental strength that I kept focusing on and just trying to, although in that second set I wasn't hitting the ball, I was just trying to regroup."

Clijsters' quarterfinal opponent will be 18th-seeded Li Na of China, who advanced with a relatively easy 6-2, 6-3 victory over 26th-seeded Italian Francesca Schiavone in 1 hour, 10 minutes at Louis Armstrong Stadium.