LONDON - No. 1-seeded Novak Djokovic and No. 2 Andy Murray have yet to lose a set, let alone a match, so far at Wimbledon.
The way things have been going at the All England Club this fortnight, that's quite an accomplishment.
Rafael Nadal, a 12-time Grand Slam champion, was beaten in the first round. Roger Federer, owner of a record 17 major titles, went out in the second, as did four-time major champ Maria Sharapova. Five-time Wimbledon winner Serena Williams' 34-match winning streak ended in the fourth round.
And on and on it's gone, with no top-20 player other than Murray left on his side of the draw, and a record-equaling number of withdrawals or mid-match retirements because of health problems.
"Everyone was a bit on edge, a little bit uptight," reigning U.S. Open champion Murray acknowledged, "because of what was happening with the injuries, withdrawals, upsets and stuff."
He and Djokovic have made it all look so routine, though, heading into the men's quarterfinals Wednesday.
On the top half of the bracket, Djokovic -- a six-time Grand Slam titlist and the only remaining past Wimbledon winner -- will face No. 7 Tomas Berdych of the Czech Republic, the 2010 runner-up. No. 4 David Ferrer of Spain plays No. 8 Juan Martin del Potro of Argentina, the 2009 U.S. Open champion and the third man who hasn't dropped a set through four matches.
On the bottom half, it will be Murray against 54th-ranked Fernando Verdasco of Spain, and No. 24 Jerzy Janowicz against his Davis Cup teammate and pal, 130th-ranked Lukasz Kubot, in a match between the first two Polish men to reach a Grand Slam quarterfinal since 1980.
"Magical," Janowicz said.
In keeping with the unpredictable nature of the tournament, whoever wins the women's title will be a first-time Grand Slam champion. Thursday's semifinals are 2012 runner-up Agnieszka Radwanska of Poland against 23rd-seeded Sabine Lisicki of Germany (who beat Williams on Monday), and 2007 runner-up Marion Bartoli of France against 20th-seeded Kirsten Flipkens of Belgium.
Janowicz and Kubot will be playing in the quarterfinals at the grass-court Grand Slam tournament for the first time, as will Verdasco and del Potro. Ferrer lost at that stage last year.
The other three have much more solid Wimbledon bona fides: Murray (2012) and Berdych (2010) have been the runner-up, while Djokovic won the title in 2011.
"I feel good about myself in this moment. I think I actually play a better tennis on grass than I played two years ago, when I won this tournament," said Djokovic, who never before had won every set he played in five previous trips to the Wimbledon quarterfinals. "For now, I'm feeling good. I'm No. 1 of the world. I have no reason to be concerned about my game."
He is bidding to reach the semifinals for a 13th consecutive Slam, the second-longest streak in men's tennis history, behind only Federer's 23-semifinal run.
Djokovic has played in seven of the last 10 major finals, and he's combined with Federer and Nadal to win 31 of the past 33 trophies.
The only other men in those eight-plus years to win a Grand Slam title were Murray and del Potro. Murray has elbowed his way into the upper echelon, turning the Federer-Nadal-Djokovic Big 3 into a Big 4 lately, participating in the finals of the last three major tournaments he entered (he missed this year's French Open with a bad back).
Murray memorably broke down in tears while addressing the Centre Court crowd after losing last year's championship match at Wimbledon to Federer. Murray was the first British man to reach the final since 1938 and fell one win short of giving the country its first male champion at Wimbledon since Fred Perry in 1936.
Said Murray that day, his voice cracking: "I'm getting closer."
He was, indeed.
A month later, in the same arena, he defeated Federer for a gold medal at the London Olympics.
And then, in September, Murray edged Djokovic in five sets at Flushing Meadows to snap an 0-4 drought in Grand Slam finals. He followed that up by getting to the Australian Open final in January, only to lose to Djokovic.
"You do learn a lot from losing. I'd lost enough big matches to want to win one and learn from how I managed to win a major event," Murray said. "The one thing I would say from having experienced it is just I kept trying to work harder and harder, try and keep improving my game from losses. That's why I eventually managed to sort of get over that final hurdle."
He has won 15 matches in a row, and 21 of his past 22, on grass courts, going into Wednesday against Verdasco, a former top-10 player whose only major semifinal came at the 2009 Australian Open.
This will be their 10th meeting on tour; Murray leads 8-1. They've known each other for years, dating to when Murray moved to Spain to train at a tennis academy there.
"Going to be difficult to beat him, also with the crowd and everything," Verdasco said. "I mean, you need to have faith and try your best to try to win."
Berdych also has a daunting head-to-head record to overcome: He is 2-13 against Djokovic. But Berdych might derive some hope from knowing he beat Djokovic the last time they met, on clay at Rome in May, and also the only time they've played each other on grass, in the 2010 Wimbledon semifinals.
Berdych eliminated Federer in the quarterfinals that year, but lost to Nadal in the final.
"I know how it is to beat Roger here," Berdych said. "It's really nice."
No chance of facing quite that same sort of lineup this time around, thanks to all of the early surprises. But if Berdych wants to earn his first Grand Slam title, he will need to get past Djokovic, of course, and perhaps Murray, too.