This year's Australian Open has already seen a couple of big-name exits with British number one Cameron Norrie crashing out of the men's draw and American star Coco Gauff losing her first-round match with China's Wang Qiang in the women's tournament.
And more surprises could be in store in the coming days in Melbourne.
One of the closest betting heats in the first round of matches in the women's singles sees two former Grand Slam champions lock horns when Sloane Stephens takes on Emma Raducanu. You can follow the action via our Sports Live Streaming platform.
Raducanu has become an immensely popular figure in British tennis since becoming the first qualifier in the Open Era to win a Grand Slam with her US Open triumph last year.
She did not drop a single set on her way to lifting the title and it will go down as one of the most special major successes in the history of the women's game.
However, since her title victory in New York, Raducanu has struggled.
She is 8/11 to win her match with Stephens, who is 11/10 to advance, and there could be an upset.
Since winning the US Open, Raducanu has lost four of her six matches and a coaching change and limited training means her preparations have not been great.
Stephens is by no means in red-hot form herself but is a former Australian Open semi-finalist, likes the hard courts in Melbourne and can count on her experience to potentially inflict a first-round defeat on one of Britain's most exciting young talents.
Another British star on display on day two of the tournament is Dan Evans and although he is well-fancied at 3/10 to beat David Goffin, who is 5/2 to prevail, he may not have things all his own way in the first-round clash.
Evans is in good shape, having reached the semi-final of the Sydney International after winning all three of his matches at the ATP Cup for Great Britain.
He is certainly worth consideration to progress but Belgian Goffin was also looking good in the Sydney International before having to withdraw from his quarter-final contest with Murray and he has also reached the last eight of the Australian Open before. The prices may not be an entirely fair reflection of how this one could go.
Last year's Wimbledon runner-up Matteo Berrettini, meanwhile, was pushed hard by one unseeded American in the Australian Open first round and the same could happen in the second, which starts on Wednesday.
Berrettini beat Brandon Nakashima 4-6 6-2 7-6 6-3 at the Margaret Court Arena and although he is 1/9 to win his next match against 11/2 shot Stefan Kozlov, he could also face some resistance.
Despite a memorable 2021, Berrettini has struggled in the last few months.
He lost his one and only match at the ATP World Tour Finals against Alex Zverev before falling to defeats in two of his three matches at the ATP Cup.
His form is therefore not ideal heading into the season's first Grand Slam and that should give Kozlov some hope.
The 23-year-old breezed past Czech Jiri Vesely in straight sets in his opener and won the US Challenger Campaign as eighth seed back in November.
Canadian star Denis Shapovalov has never made it beyond the third round of the Australian Open and could face some difficulty even reaching that stage this time around.
In the second round on Wednesday, he is set to lock horns with Kwon Soon-woo of South Korea and it may not be a straightforward assignment.
First of all, Shapovalov was far from untouchable in his opening contest with Laslo Dere, dropping a set and a total of 22 games in the John Cain Arena.
He performed well for Canada in the ATP Cup but otherwise had little preparation for the Australian Open.
As for Soon-woo, he made it to the last 16 of the Adelaide International earlier this month and defeated the tournament's fifth seed Lloyd Harris in the process.
He edged past Holger Rune in the first round of the Australian Open, albeit after dropping two sets, and could be a more challenging opponent for Shapovalov than the odds suggest.
Shapovalov is 2/7 to progress with Soon-woo available at 11/4 to win the match. Punters can also back the contest to feature five sets at 3/1.
And the odds also suggest a one-sided affair will unfold when Swiss star Belinda Bencic takes on Amanda Anisimova in the second round of the women's singles on Wednesday. Bencic is 4/7 to win with Anisimova 11/8.
But Anisimova arguably deserves more credit given she already has a title to her name in 2022.
The 20-year-old won this month's Gippsland Trophy a matter of weeks ago, beating Aliaksandra Sasnovich in the final and having also knocked out the tournament's third seed Daria Kasatkina and fifth seed Sorana Cirstea earlier in the competition.
Bencic can be a skillful operator and reached the quarter-finals of the Sydney International but should be wary of the threat posed by Anisimova in Melbourne.