MELBOURNE, Australia – Serena and Venus Williams are on track for a sisters semifinal at the Australian Open after fourth round wins.

Venus advanced to the quarterfinals for the seventh time by beating Italy’s Francesca Schiavone 3-6, 6-2, 6-1 in the opening match Monday on Rod Laver Arena.

She’s a win away from a possible showdown with her younger sibling.

Defending champion Serena had a 6-4, 6-2 win over Australia’s Sam Stosur.

Serena, who has won the Australian each odd-numbered year since defeating Venus in the 2003 final, conceded only seven points on serve in the match, including one double-fault in the second set.

“I can’t believe it — Sam beat me last time pretty convincingly, so I knew I had to do real good,” Serena Williams said. “I think my serve was pretty good today.”

Stosur, seeded 13th, beat Williams in their last match and had match points before losing the match prior to that. On Monday, she didn’t get close, and was the last Australian eliminated from the women’s draw.

There’s two Chinese women into the quarterfinals, for the first time ever at a Grand Slam tournament.

Li upset No. 4-seeded Caroline Wozniacki 6-4, 6-3 in a 98-minute match featuring 12 service breaks to join Zheng Jie, the 2008 Wimbledon semifinalist, in the last eight. Zheng is on the other half of the draw.

“Nothing better,” Li said, smiling, “Yeah, I mean good for us.”

Li already has reached the quarterfinals at Wimbledon and went out at that stage in the last U.S. Open. She beat Williams in the quarterfinals at the Beijing Olympics in their only previous meeting, but she wasn’t drawing too much from that.

“It was good experience for me, for my tennis, also,” Li said. “But I just want to forget, because I will play her again. So I didn’t want always think about the last match. I want to look forward.”

Williams has won seven singles majors and reached the final of the Australian Open in ‘03, losing to her younger sister Serena, in her best run at Melbourne Park.

She struggled to hold serve in the first set against Schiavone but was in command by the end, when she won the last six games after the 29-year-old broke her to open the third set.

“Francesca was playing so well, she was so tenacious, she has so much speed,” Williams said. “I had a little bit of a slow start.”

The Williams wins extended a streak in which at least one American woman has reached the Australian Open quarterfinals every year since 1977.