MELBOURNE, Australia -- After three days of relatively drama-free tennis, could we be in store for a major upset?
Here's how you can catch all the action, including Serena Williams, on Day 4 at Melbourne Park.
How to watch every match
Matches begin on ESPN3 and the ESPN App at 7 p.m. ET. Click here to watch.
Matches begin on ESPN2 & WatchESPN at 9 p.m. ET. Click here to watch.
To view starting times for upcoming days, click here.
Where to get tournament live scores
Our real-time scoreboard, updated stats and social handles can be found all in one spot: Australian Open CourtCast.
Schedules
To view a full schedule of Day 4 at the Australian Open, click here.
Notable Day 4 matches
No. 17 Caroline Wozniacki versus Donna Vekic, second match at Rod Laver Arena (Watch)
Wozniacki will never win a Grand Slam title, right? Probably not. But maybe, just maybe, she has what it takes to go all the way at Melbourne Park. The Dane is still just 26, middle age in tennis terms, but it's not unheard of for a talented player to break through for a maiden Slam at her age. The former world No. 1 blitzed Australia's Arina Rodionova in straight sets to open her tournament and next faces Croatia's Vekic, herself a straight-sets victor over an unheralded local, Lizette Cabrera. This pair have met only once, at this same tournament four years ago, with Wozniacki winning comfortably. If she repeats the dose on Day 4, it could be the confidence-boosting victory she needs to start dreaming of a long-overdue Grand Slam title.
No. 3 Milos Raonic versus Gilles Muller, third match at Margaret Court Arena (Watch)
Raonic has the game to overpower anyone in the world, and it's just a matter of time before he sheds his titleless drought, right? As he surged to the semifinals at this tournament last year and the final of Wimbledon a few months later, many experts were sure Raonic would take home some serious silverware at some stage. But will it be here, at Melbourne Park, in 2017? Perhaps. He first has to get past Muller -- the world No. 28 who has a 2-0 record against the big Canadian. It's the sort of match a serious contender shouldn't lose. Over to you, Milos.
No. 6 Gael Monfils versus Alexandr Dolgopolov, third match at Hisense Arena (Watch)
This one could be worth the price of admission alone for those lucky enough to be in Melbourne. Two of the most exciting and enigmatic players on the tour will lock horns in an attempt to win through to the third round. Monfils, the sixth seed, will be favored to progress, having seemingly ironed out much of the inconsistency that blighted his early career. The Frenchman waltzed past the Czech Republic's Jiri Vesely to open his campaign and should be confident of at least matching, if not surpassing, last year's quarterfinal exit. But the unseeded Dolgopolov is exactly the type of opponent a big name hates facing at this stage of a tournament. He has the weapons to push anyone in the world when the mood takes him. Strap yourselves in.
No. 2 Serena Williams versus Lucie Safarova, 3 a.m. ET at Rod Laver Arena (Watch)
Boasting a 9-0 record against Safarova, Williams could perhaps be excused of already looking ahead to her third-round battle. She did enough to account for hard-hitting Swiss youngster Belinda Bencic 6-4, 6-3 in the opening round. Williams described it as "one of the toughest first-round matches I have played," while Safarova edged past Belgian Yanina Wickmayer in three tough sets. Williams, who lost her No. 1 ranking to Angelique Kerber last year, will be looking to prove she's ready to reclaim her crown. Look out, Lucie.
No. 9 Rafael Nadal versus Marcos Baghdatis, following Williams-Safarova (Watch)
Aussie fans have a longstanding love affair with Baghdatis after the Cypriot's incredible rags-to-riches run to the final of the 2006 Australian Open. Often labeled an honorary Australian by the strong and vocal Greek community in Melbourne, Baghdatis could again ignite Rod Laver Arena when he lines up against No. 9 seed Nadal. Baghdatis has a woeful record against the Spaniard, winning only one of nine matches, but Nadal, the battle-weary warrior, is far from his the player he was even two years ago. Still, Nadal, who says he is feeling healthy and fit, brushed past Germany's Florian Mayer in the first round, while Baghdatis cruised through to the second round when Russian Mikhail Youzhny retired while trailing 6-3, 3-0.
Notable nuggets
It's been awhile since Novak Djokovic lost a set in the first week here. He has won 51 sets in a row dating back his second-round win against Ivan Dodig in 2011, 7-5, 6-7 (8), 6-0, 6-2.
Agnieszka Radwanska's opponent ended a 19-year drought in her last round. On Tuesday, Mirjana Lucic-Baroni beat Qiang Wang for the Czech's first win at the Aussie Open since 1998. She beat Rennae Stubbs that year before falling to reigning French Open champion Iva Majoli.
It's the 20th anniversary of the great scorcher of 1997. On Jan. 19, 1997, with temperatures in excess of 100 degrees -- and on-court temperatures reaching 140 degrees -- four of the women's top eight seeds were ousted in the fourth round, most notably No. 1 seed Steffi Graf, who lost stunningly to Amanda Coetzer.
Ivo Karlovic takes the court a round after delivering 75 aces. Three times in his career, Karlovic has smacked 60 or more aces in a match; no one else has ever done it twice.