PARIS -- In the first set, Novak Djokovic angrily busted his racket. At the end, he happily threw a punch at the red clay he's so eager to conquer.
Mostly he tried to keep his emotions in check Monday at the French Open while grieving the death of his childhood coach.
Djokovic lost a set for the first time in the tournament, then rallied to reach his 16th consecutive Grand Slam quarterfinal by beating Philipp Kohlschreiber 4-6, 6-3, 6-4, 6-4.
Seven-time champion Rafael Nadal also advanced, celebrating his 27th birthday by beating Kei Nishikori 6-4, 6-1, 6-3. Afterward the center court crowd serenaded Nadal with "Joyeux Anniversaire" -- "Happy Birthday" -- and he was presented with an enormous cake.
Djokovic's celebration was more tempered. He played for the first time since learning that his first coach, Jelena Gencic, had died in Belgrade at age 76.
She mentored him for about five years, starting when he was 6.
"I feel even more responsible now to go all the way in this tournament," he said. "I want to do it for her, also, because she was a very special person in my life."
He recalled his grandfather's death, when Djokovic was in the midst of a tournament and went on to lose in the final.
"The experience that I had with my grandfather's passing away last year helped me a little bit to kind of stay tough this time," he said, "because it took me a long time last year to recover. It was very emotional.
"I'm handling it better. I'm trying to focus my thoughts on the nicest memories."
The No. 1-ranked Djokovic will next play 35-year-old Tommy Haas, who became the oldest French Open men's quarterfinalist since 1971 by beating Mikhail Youzhny 6-1, 6-1, 6-3. Haas is also the oldest man to reach the quarters at any major event since Andre Agassi at the 2005 U.S. Open.
Victoria Azarenka swept the final nine games and advanced to the women's quarterfinals by beating 2010 champion Francesca Schiavone 6-3, 6-0. Azarenka will next play Maria Kirilenko, who reached her first French Open quarterfinal by ending the surprising run of 67th-ranked American Bethanie Mattek-Sands, 7-5, 6-4.
Nadal trailed early in each of his first three matches, but he played from ahead against Nishikori, the first Japanese man to reach the fourth round at Roland Garros since 1938.
"I played better than in previous days," Nadal said.
Riding a 19-match winning streak, Nadal seeks to become the first man to win eight titles at the same Grand Slam event. He won a record seventh French Open championship last year and is 56-1 at Roland Garros.
His opponent Wednesday will be the winner of the match between No. 7-seeded Richard Gasquet and No. 9 Stanislas Wawrinka.
While Nadal is trying to repeat, Roland Garros is the only major tournament Djokovic has yet to win, and he hopes to become the eighth man to complete a career Grand Slam.
The six-time major champion was subdued at the start against Kohlschreiber but gradually became more animated. While the abuse of his racket when he fell behind didn't inspire an immediate turnaround, his shots began to carry more sting in the second set, and he was quicker to pounce on balls near the net.
He repeatedly escaped trouble with his serve, erasing 11 of the 13 break points he faced, and avenged a straight-sets loss to Kohlschreiber in the third round at Roland Garros in 2009.
Haas became a first-time Roland Garros quarterfinalist in his 12th appearance at the tournament, a record for such a breakthrough. He's the first German man to reach the final eight since Michael Stich and Bernd Karbacher in 1996.
And he's the oldest men's quarterfinalist at Roland Garros since 39-year-old Istvan Gulyas in 1971.
"These are cool stats sometimes to hear," said Haas, who is mounting a comeback from injuries that sidelined him for more than a year. "I feel like I'm riding a wave that I hope to continue as long as I can. I'm going out there and I try to improve my game as much as I can, and to be in this situation is spectacular."
Seeded No. 12, Haas needed 13 match points to beat John Isner in a third-round marathon, but his victory over Youzhny took less than 90 minutes. By the second set Youzhny was so frustrated he demolished his racket by banging it nine times against his changeover chair.
"Bad luck for that racket," Youzhny said.