MELBOURNE, Australia — Being a favorite with the British bookmakers worked against Andy Murray at the Australian Open.

No. 14 Fernando Verdasco of Spain rallied to beat the 21-year-old Scot 2-6, 6-1, 1-6, 6-3, 6-4 on Monday to reach the quarterfinals at the season's first major.

The fourth-seeded Murray saved two match points after falling behind 40-0 in the last game but wasn't able to fend off a third, dumping a backhand into the net.

Murray, who lost in the U.S. Open final last year to Roger Federer, was attempting to become the first British man since 1936 to win a Grand Slam singles title.

After recent wins over No. 1-ranked Rafael Nadal and No. 2 Federer, Murray had become a favorite to beat them both for the Australian title.

"I don't know if I'll be the favorite for a Slam in the next year or so after today," Murray said, responding to questions about the extra pressure of expectations. "But it doesn't really bother me.

"If I'm the favorite to win, whatever, I play the same as I am when I'm the underdog."

Verdasco, a key player in Spain's Davis Cup final triumph in Argentina, next plays the winner of the later match between 2008 runner-up Jo-Wilfried Tsonga and American James Blake.

Verdasco saved two break points in the pivotal sixth game of the fifth set, firing aces when he needed them and forcing errors from the other side. He broke Murray in the subsequent game to push his advantage.

"I was feeling confident and fit," Verdasco said. "I just tried to play my game."

His fellow Spaniard Nadal had to go the distance Monday to reach the quarterfinals, ousting 2007 runner-up Fernando Gonzalez 6-3, 6-2, 6-4.

The two previous fourth-round matches on Rod Laver Arena were cut short when players retired with illness or injuries. A third match was over quickly, with Svetlana Kuznetsova's win over Zheng Jie on Hisense Arena lasting five games before the Chinese player retired with an injured left wrist.

Second-seeded Serena Williams lost the first set to Victoria Azarenka but was up a break in the second when her tearful and dizzy rival from Belarus had to quit because of a vomiting virus.

"Honestly, I got worried," Williams said. "She started walking really slow. The last thing she would want to do, to me, would be fall. It was just weird. I was actually really worried."

In the opening match on center court, No. 6 Gilles Simon was leading 6-4, 2-6, 6-1 when his friend and fellow Frenchman Gael Monfils retired with a right wrist problem.

That brought top-ranked Nadal and Gonzalez on earlier than expected to determine who would meet Simon in the next round.

Nadal ran off 12 of the first 13 points and broke Gonzalez twice in the first set en route to his third quarterfinal appearance at Melbourne Park in his last three trips.

The 22-year-old Spaniard went down a break in the third set but rallied to win five straight games and six of the last seven.

Gonzalez, who beat Nadal here in the quarterfinals on his run to the final two years ago, was coming off a difficult third-round win, when he rallied from two sets down to beat Richard Gasquet 12-10 in the fifth.

Matches early Monday were over surprisingly quickly, considering conditions were sunny and mild with temperatures around 75.

Williams was up a service break at 4-2 in the second set after No. 13 Azarenka had won the first set 6-3.

Azarenka, serving at 30-30, wobbled back into the shade at the rear of the court, holding her face and choking back tears as she tried to regather herself.

She needed a medical timeout earlier in the set and left the playing arena. She returned for 1 1/2 games but was unable to continue and was helped from the court soon after by two trainers.

"The doctors didn't want me to keep going, but I wanted to keep trying and see how I do," she said. "But it was probably not a very good idea because it just gave me even more trouble after."

Azarenka was taking the match to Williams, with both women going for winners constantly.

At 3-5 in the first set, Williams double-faulted for the second time to give Azarenka a set point, then loudly cursed her first serve, earning a warning from the umpire for an audible obscenity and sending a backhand long on the next point.

Things got better for Williams as she saved three break points in her opening serve of the second set in a game that went to deuce five times, then broke Azarenka to pull ahead at 2-1.

Azarenka appeared to become ill after pulling within 3-2 and went off court. Williams took advantage of the time to get her ankles retaped.

Azarenka said she'd been feeling sick all morning.

"I woke up at 6 a.m. and I was throwing up all the morning and just felt weak," she said. "Once I got to the court, I went to see the doctor, I felt a little bit better.

"It's very disappointing for me that I played that well and I couldn't handle a little bit more because it was really close games."

Williams, seeking a 10th Grand Slam singles title, next plays 2004 U.S. Open champion Svetlana Kuznetsova, who advanced when Zheng retired while trailing 4-1 in the first set after tumbling onto her wrist at the end of the third game.

Williams and Kuznetsova are the only major winners still in the women's draw.

The winners of Monday's two completed women's matches meet in the quarterfinals.

Carla Suarez Navarro, the 20-year-old Spaniard who had an upset win over seven-time Grand Slam winner Venus Williams in the second round, beat No. 21 Anabel Medina Garrigues 6-3, 6-2.

Olympic gold medalist Elena Dementieva made the quarterfinals for the first time in 11 years at Melbourne Park with a 6-2, 6-2 win over Slovakia's Dominika Cibulkova.

The fourth-seeded Dementieva, who reached the finals at the French and U.S. Opens in 2004 but has not been to a Grand Slam championship match since, extended her winning streak to 14 matches. She won two titles in tuneup events.

She could take the No. 1 ranking by winning the tournament.

"It's a great motivation," she said.