Women's fourth round matches on Monday at the Australian Open sees Maria Sharapova take on Dominika Cibulkova, Victoria Azarenka face Sloane Stephens, Agnieszka Radwanska play Garbine Muguruza and Jelena Jankovic battle Simona Halep.
Meanwhile, men's Round 4 matches will pit Rafael Nadal up against Kei Nishikori, Roger Federer against Jo-Wilfried Tsonga, Andy Murray against Stephane Robert and Grigor Dimitrov against Roberto Bautista Agut.
Women's fourth round action on Monday begins on Rod Laver Arena from 11am EST with what looms as a terrific encounter between former champion and world No. 1 Sharapova up against 20th-seeded Slovak Cibulkova.
Sharapova is now the second highest-ranked player left in the women's draw at No. 3 following Serena Williams' upset loss to Ana Ivanovic on Sunday, but the Russian three-time Grand Slam winner will have her work cut out against Cibulkova.
The Slovak 24-year-old is in the form of her career so far in Melbourne recording emphatic wins over Francesca Schiavone, Stefanie Voegele and Carla Suarez Navarro without dropping a set to advance into the fourth round for the second time in Melbourne, and just sixth time at a major in 26 attempts.
The pocket rocket's best major performance is a semi-final appearance at the 2009 French Open but this already equals her best ever performance in Melbourne, and best effort at any major since Roland Garros in 2012.
Meanwhile, Sharapova hasn’t had the easiest time winning into the fourth round beating Bethanie Mattek-Sands and Alize Cornet in straight-sets, but only overcome Karin Knapp 10-8 in the third set on a scorching hot Melbourne day in the second round.
Sharapova and Cibulkova have met five times on the WTA Tour previously with the Russian holding a narrow 3-2 advantage.
Two of those matches have been at Grand Slams with Cibulkova winning in the quarter finals at Roland Garros in 2009 and then Sharapova also in the quarters at Wimbledon 2011.
Next up on Rod Laver Arena in women's Round of 16 action sees American 13th-seed Stephens try to continue to go from a potential Grand Slam threat to a genuine title contender this fortnight when she takes on defending champion and world No. 2 Azarenka.
Azarenka is now the highest seeded player left in the Australian Open as she looks to defend her title and so far the 24-year-old Belarusian has had little trouble advancing to the fourth round beating Johanna Larsson, Barbora Zahlavova Strycova and Yvonne Meusburger all in straight-sets.
However, 20-year-old 13th-seeded Stephens is without doubt one of the emerging stars of the game and this could be her chance to take the next step in her young career.
So far, she has beaten Yaroslava Shvedova, Anna Tomljanovic and Elina Svitolina to move into the fourth round for the second straight year at the Australian Open.
Azarenka and Stephens have met previously just the once with the Belarusian prevailing at last year's Australian Open 6-1, 6-4 in the semi finals.
The first men's fourth round match on Rod Laver Arena pits world No. 1 Nadal up against Japan's 16th-seed Nishikori.
Nadal has been in ominous form winning his way into the fourth round with the Spanish 2009 Australian Open winner so far having thrashed Bernard Tomic, Thanasi Kokkinakis and Gael Monfils.
Meanwhile, Nishikori has advanced to the Australian Open Round of 16 for the third successive year by beating Marinko Matosevic, Dusan Lajovic and Donald Young in the first three rounds.
It's a massive ask, though, for Nishikori just to make a contest of it given Nadal's brutal form so far.
The pair have previously clashed five times on the ATP Tour with Nadal winning on each occasion with the most recent being a 6-4, 6-1, 6-3 triumph at last year's French Open also in the Round of 16.
The night session on Rod Laver Arena for Monday then begins with what promises to be a can't-miss men's fourth round match-up between four-time Australian Open champion Federer and former finalist Tsonga.
Federer and Tsonga have met one another 13 times previously with the Swiss 32-year-old leading 9-4 including twice at Grand Slams in 2013.
Federer beat Tsonga in a five-set classic in last year's Australian Open quarter finals and then in the same round, beating him in straight-sets at Roland Garros.
The Swiss master has won his way through to the Australian Open fourth round without dropping a set with comfortable wins against James Duckworth, Blaz Kavcic and Teymuraz Gabashvili.
Meanwhile, Tsonga has advanced by downing Filippo Volandri, Thomaz Bellucci and Gilles Simon all in straight-sets as well.
The night on Rod Laver Arena will then conclude with a women's match-up between world No. 5 Pole Radwanska and unseeded Spaniard Muguruza.
Muguruza might only currently be ranked No. 38 in the world, but she is vastly more talented that with a big all-round game that has the 20-year-old earmarked as another future star of the women's game.
Like Stephens, this could very well be her fortnight to put in a breakout performance to ensure nobody ever takes her lightly again and already she has made the fourth round for the first time at any major tournament.
Muguruza has beaten Kaia Kanepi, Anna Schmiedlova and Caroline Wozniacki to advance to the fourth round.
However, Radwanska is a player to have already arrived as a genuine star with the only thing missing from her resume now being a Grand Slam title.
The fifth-seed has made a final at Wimbledon in 2012 and is now into the Australian Open fourth round for a fourth straight time by beating Yulia Putintseva, Olga Govortsova and Anastasia Pavlyuchenkova along the way so far.
Radwanska and Muguruza have played one another just the once before on tour with the Pole winning in straight-sets at Miami in 2012.
Fourth round singles action begins on Hisense Arena with another former women's world No. 1 in action when Jankovic takes on 11th-seeded Romanian Halep.
Jankovic has been in good form to qualify for the fourth round beating three Japanese opponents all without dropping a set – Misaki Doi, Ayumi Morita and Kurumi Nara.
The 28-year-old Serb has struggled for the most part since becoming world No. 1 in 2008 only making it past the fourth round at any Grand Slam twice in 20 attempts since losing the US Open final of 2008.
Meanwhile, Halep is yet another rising star of the women's game and her Australian Open so far has seen her beat Katarzyna Piter, Varvara Lepchenko and Zarina Diyas in the first week.
Halep is in just her second fourth round at a Grand Slam but second straight having also made the Round of 16 at last year's US Open.
Jankovic and Halep have previously played three times with the Romanian winning two of those.
The other fourth round singles match-up on Hisense Arena in the day session is a men's match-up between three-time Australian Open runner-up and reigning Wimbledon champion Murray against unseeded Frenchman Robert.
Robert at 33 years of age is having the Grand Slam of his career already at this year's Australian Open with him remarkably only earning a spot in the draw due to a withdrawal after he lost in qualifying.
The world No. 119 has since gone on to beat Aljaz Bedene, Michal Przysiezny and Martin Klizan to qualify for the fourth round at any Grand Slam for the first time.
Now taking on the world No. 4 Murray is a whole other level for the Frenchman to have to rise to with the Scot so far having beaten Go Soeda, Vincent Millot and Feliciano Lopez all in straight-sets.
Murray might have come up short in three finals in Melbourne, but the fact that he has got that far on three occasions shows just how much he enjoys the Australian Open and he will at least be wanting to give him another chance at the title in 2014.
Murray and Robert have never previously faced one another.
The night session on Hisense Arena will then conclude in the final men's fourth round match-up between rising Bulgarian star Dimitrov and unseeded Spaniard Bautista Agut.
Bautista Agut has so far been the giant-killer of the Australian Open beating Tim Smyczek, Juan Martin Del Potro and Benoit Paire to make it through to the fourth round of a Grand Slam for the first time.
Dimitrov is also into his very first Grand Slam fourth round having beaten Bradley Klahn, Yen-Hsun Lu and Milos Raonic as the talented 22-year-old No. 22 seed looks to be on target of turning his huge potential into results now in 2014.
Dimitrov and Bautista Agut have met just the once before with the Spaniard winning last year in Beijing 6-4, 6-2.