The player with the best chance of eclipsing that is Serena Williams who is in pursuit of her 22nd, and was not tested Margarita Gasparyan, taking the opening set 6-2.

Maria Sharapova also weathered a fightback when she beat pint-sized American Lauren Davis 6-1, 6-7 (5/7), 6-0, helped by a strategic break and change of dress, for her 600th career win.

Novak Djokovic of Serbia signs autographs after defeating Giles Simon of France in their fourth round match at the Australian Open tennis championships in Melbourne, Australia, Sunday, Jan. 24, 2016.

Williams has defeated Sharapova in 18 of 20 meetings, including the 2015 Melbourne final.

Top-seeded Novak Djokovic and No. 7 Kei Nishikori first played at the French Open in 2010, where Djokovic won in straight sets, and the Serbian player holds a 5-2 edge overall.

Federer watched Djokovic's match, before going out to beat No. 15 David Goffin 6-2, 6-1, 6-4 in a match that finished after midnight, and the error toll didn't bring him any joy. The world number one hasn't become the dominant force he is without winning a few tight matches on the way though, and he raised his game, improving his first serve percentage from 56% to 75% and hitting fewer than half as many unforced errors as in the fourth. The Swiss maestro, who turned 34 last August, is still playing his most aggressive tennis to date and left very little to his opponents during the first three matches - including the talented Dolgopolov and Dimitrov.

"The biggest thing is he doesn't miss", Nishikori said, "He doesn't give you any free points". Sharapova is trying to play positive mind games to rid herself of that dreaded record of having not beaten Williams in such a long time. "I got myself into the quarter-final of a Grand Slam". "There's no reason I shouldn't be looking to improve and to getting my game in a better position than any other previous round. It's only going to be tougher, especially against Serena". It was an ugly match - one that Simon will think of for years, as he had the indestructible world No. 1 on the ropes all afternoon - punctuated with Djokovic overcorking shots, slamming 110 miles per hour forehands in the bottom of the net, ripping backhands two feet long and, inexplicably continuing to attempt drop shots after the sneaky fast Simon kept running them down or they went short or wide.

But Djokovic looked out-of-sorts against the wily Frenchman, who took the pace out of the match by slicing and looping the ball, as the defending champion made exactly 100 unforced errors in four hours and 38 minutes. It's different conditions [here], but I hope I can make some changes and try to play better.

"But I played a quality player who took out Federer past year... he is not afraid to play big tennis on a big stage". "It doesn't concern me for the next one".

Relegated to Margaret Court Arena for the first time in nine years, Djokovic took down No. 28 Andreas Seppi 6-1, 7-5, 7-6 (6) in the third round at the Australian Open.

"I feel if I can just continue to play well, then it could be good", the six-times champion said after celebrating her victory with a graceful twirl.

"Playing against a player like Gilles you can expect a lot of rallies", said Djokovic. It's been seven years since Suarez Navarro made a quarterfinal here.

"I know a lot of players wanted me to win this match".