Las Vegas: Spain's Fernando Verdasco advanced to the quarterfinals of the Tennis Channel Open on Wednesday, beating Thailand's Danai Udomchoke 6-1, 5-7, 6-2 in round-robin play. The fifth-seeded Verdasco had four double faults while losing the second set, and then took advantage of Udomchoke's four double faults in the third. Verdasco also defeated Paul-Henri Mathieu of France in three sets on Monday, finishing 2-0 in his round-robin group. "I was a little bit unfocused in the second set," Verdasco said. "After losing the second set, I asked if I needed to win. When they said 'yes,' that refocused me." Also, eighth-seeded Benjamin Becker of Germany defeated Gustavo Kuerten of Brazil, 6-4, 6-3. Kuerten, ranked No 1 on the ATP Tour on Dec. 4, 2000, underwent hip surgery in 2004. He competed in just one singles match last year and only got back on the court last month in Chile. In other matches, unseeded Sam Querrey beat sixth-seeded Julien Benneteau of France, 6-2, 7-6 (3); fourth-seeded Jurgen Melzer of Austria defeated Michael Llodra of France, 6-4, 2-6, 7-5; Igor Kunitsyn of Russia beat Stefan Koubek of Austria, 6-2, 6-2; and Feliciano Lopez of Spain got past Nicolas Mahut of France, 3-6, 6-3, 7-6 (3). In the night session, Sweden's Thomas Johansson needed only 46 minutes to beat Yen-Hsun Lu 6-0, 6-1. Lu, who lost in the tournament's main event draw phase, replaced Vince Spadea in round-robin action after Spadea withdrew earlier today with an injured left ankle. Johansson will meet Lleyton Hewitt on Thursday with the winner advancing to Friday's quarterfinals. Johansson, ranked No 90 in the world, had nine aces, including seven in the second set. He won 57 of the match's 84 points. Also, brothers Bob and Mike Bryan, the defending champions and the event's top-seeded doubles team, won a tiebreaker 12-10 against Wesley Moore and Todd Perry to cap a 6-3, 1-6, 1-0 victory.