MELBOURNE, Australia -- When 13th-seeded John Isner retired from his first-round match Tuesday with a recurring ankle injury, the U.S. men's hopes at the Australian Open fell squarely on another set of broad shoulders, and 51st-ranked Sam Querrey was more than up for the challenge.
The 6-foot-6 hard-serving Californian, who ranked as high as 17th in 2011 before he was beset by a series of injuries, sounded as though he's ready for a career resurgence after his commanding 6-2, 6-3, 6-4 victory Wednesday over No. 23 seed Ernests Gulbis.
"It was just an overall solid match for me, the best I've played in a long time and I just feel like I'm playing really well right now and hopefully I can keep it up," Querrey said.
Lauren Davis also won and reached her first-ever third round at a major.
Madison Keys, 18, who came into Melbourne having reached two semifinals in her past three tournaments, was leading 4-1 in the third set before losing to former Australian Open and Wimbledon semifinalist Zheng Jie 7-6 (5), 1-6, 7-5. Irina Falconi was eliminated by Ekaterina Makarova 6-2, 7-5.
"I'd obviously love to be talking about winning the match, but it's going to happen," said Keys, who is ranked a career-high 36th. "I'm learning how to deal with losses and learning from them."
Querrey, who had 24 aces in his four-set, first-round win over Santiago Giraldo, fired 19 aces, won 88 percent of his first serves and had 30 winners against 21 unforced errors in a 1-hour, 37-minute match.
"That was one of my best serving days ever," Querrey said. "But I felt like I returned really well. He has a huge serve and I felt like I did a good job of making him play on his service games, even the games he was winning."
Querrey has reached the third round here four times, including his first Australian Open as a wild card in 2007. The 26-year-old also reached the round of 16 at the US Open in 2008 and 2010, where he lost to Rafael Nadal and Stanislas Wawrinka, respectively, and at Wimbledon in 2010, losing to Andy Murray.
In 2010, Querrey won four singles titles, behind only Nadal and Roger Federer that year.
"I think with my game and the confidence I have, I really like my chances to make the fourth round," Querrey said.
And beyond that?
"I want to take it slow, but I think I can win some more matches here hopefully and then hopefully play Davis Cup and win some matches. … Definitely if I play like I'm playing right now, I think I can make a push back into the top 20, into the top 15 and into the top 10."