Six-time champion Rafael Nadal and women's No. 2 seed Maria Sharapova won in straight sets to reach the French Open's fourth round, while unseeded American Varvara Lepchenko upset 2010 winner Francesca Schiavone.
Nadal beat Eduardo Schwank of Argentina, 6-1, 6-3, 6-4 at Roland Garros in Paris yesterday. Sharapova advanced with a 6-2, 6-1 win against China's Peng Shuai.
"For the time being, everything is OK," Nadal, the men's No. 2 seed, said in a news conference. "Maybe I could improve my game a little, because the most difficult match is yet to come."
Lepchenko, 26, pulled off the surprise of the day by beating 14th-seeded Italian Schiavone, last year's finalist, 3-6, 6-3, 8-6 to move into the fourth round of a Grand Slam tournament for the first time in her career. The victory, along with Sloane Stephens's win the day before, leaves two unseeded American women in the final 16 of a major for the first time since Wimbledon in 2002.
Both No. 1 seeds are in action today. Novak Djokovic of Serbia, seeking to hold all four Grand Slam titles at the same time, plays 22nd-seeded Italian Andreas Seppi and Victoria Azarenka of Belarus meets Slovakia's Dominika Cibulkova, seeded 15th.
Roger Federer, the record 16-time men's Grand Slam singles winner, also plays today against qualifier David Goffin of Belgium.
Nadal, who celebrates his 26th birthday today, is seeking to become the first man to win seven singles titles at Roland Garros. The Spaniard next faces Argentina's Juan Monaco, who beat Canada's Milos Raonic in five sets.
Sharapova has lost five games in her first three matches as she seeks a first French Open title. She next plays Czech Klara Zakopalova in the final 16.
"I'm certainly happy with the way I performed in those rounds, in those matches, and followed through," the Russian said. "But in the next round, it starts from 0-0."
Lepchenko, who was born in Uzbekistan and became a U.S. citizen last year, beat Schiavone for the second straight time after winning in Madrid last month. She next will face Petra Kvitova of the Czech Republic, the fourth seed.
"I had to really pull it together and stay very aggressive and fight," Lepchenko said. "Until the very end, I didn't know if I'm going to win, but I kept believing in myself."
Fellow American Stephens today meets U.S. Open winner Samantha Stosur of Australia, the sixth seed. Christina McHale, the third unseeded player from the U.S. in the third round, lost yesterday to defending champion Li Na of China, the seventh seed, 3-6, 6-2, 6-1.
Britain's Andy Murray won 6-3, 6-4, 6-4 against Colombian Santiago Giraldo. The No. 4 seed showed no effects of back spasms that he said almost caused him to withdraw before his previous match two days ago.
"I woke up this morning again feeling better than I did, but that's because of the work my physio has done the last 48 hours and all the recovery work that we've done between the last match and now," Murray, who next faces Frenchman Richard Gasquet, told reporters.
Denmark's Caroline Wozniacki, who has dropped to No. 9 after starting the season atop the world rankings, lost yesterday to Estonia's Kaia Kanepi in three sets.
--Editors: Bob Bensch, Rob Gloster
To contact the reporter on this story: Danielle Rossingh in London at drossinghbloomberg.net
To contact the editor responsible for this story: Christopher Elser at celserbloomberg.net