London: Novak Djokovic is tough to beat at Wimbledon, outdoors or in.
Playing the day's first Centre Court match Friday under the retractable roof, defending champion Djokovic rallied past Radek Stepanek 4-6, 6-2, 6-2, 6-2.
When a drizzle delayed the start of the third round, tournament officials decided Djokovic's match should be played inside. An odd spectacle ensued: The roof closed as the sun came out and outside court covers came off.
The No. 1-ranked Djokovic missed opportunities to seize an early lead, failing to convert his first five break-point chances before he lost serve at love to drop the opening set. But he dominated from there, breaking in the first game in each of the final three sets.
Also advancing to the second week was Maria Sharapova, ranked No. 1 on the women's side. She rallied from a break down in the second set to beat Hsieh Su-wei 6-1, 6-4.
American Sam Querrey hit the last of his 21 aces on match point and beat No. 21-seeded Milos Raonic, 6-7 (3), 7-6 (7), 7-6 (8), 6-4. That second-round match had been suspended in the third set Thursday because of rain.
Another American, 19-year-old Sloane Stephens, lost to Sabine Lisicki 7-6 (5), 1-6, 6-2.
Djokovic's fourth-round opponent will be 34th-ranked Viktor Troicki in an all-Serbian match. Troicki beat No. 15-seeded Juan Monaco 7-5, 7-5, 6-3.
Fans were still buzzing about Rafael Nadal's second-round defeat, which ended under the roof Thursday night, when Djokovic stepped onto the same court. His slow start briefly stirred speculation about another upset.
Stepanek, at 33 the oldest man left in the tournament, repeatedly played serve and volley and had Djokovic on his heels in the early going. Djokovic hit an improbable winner that skipped off the top of the net post and still lost the first set.
Then the match quickly swung his way, and the 28th-seeded Stepanek couldn't compete with Djokovic's mistake-free play. The Serb committed just 13 unforced errors in 221 points.
The match remained entertaining even as it became lopsided. One game in the final set lasted 26 points and had Djokovic smiling at Stepanek's unconventional style, which included a belly flop in pursuit of a shot.
The other half of the draw opened up when two-time champion Nadal lost to No. 100-ranked Lukas Rosol of the Czech Republic, 6-7 (9), 6-4, 6-4, 2-6, 6-4.
Nadal had reached the past five Grand Slam finals and won his seventh French Open title this month. He also had reached the final in his past five Wimbledons, winning the title in 2008 and 2010.
His departure creates an opportunity for three-time Wimbledon finalist Andy Roddick and Andy Murray, who seeks to become the tournament's first British champion since 1936. Both are on Nadal's side of the draw.
Rosol, who had lost in qualifying for Wimbledon in each of the last five years, simply outclassed Nadal with his powerful serving and booming ground strokes. He hit cross-court backhand winners that measured 99 mph, he stepped up to whip scorching forehand returns, and he served so well that Nadal hardly tried to get to them by the final game. The last one, his 22nd, came on match point.
"I'm not just surprised; it's like a miracle for me," Rosol said. "Like just some B team in Czech Republic can beat Real Madrid (in) soccer."
Rosol won his final 13 service points, seven with aces.
"Maybe it's once in life you can play like this against Rafael Nadal on Centre Court and you can win against him," Rosol said. "You know, it's not easy. I never expect it can happen, something like this."