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Alexander Zverev, Kevin Anderson, Marin Cilic, Karen Khachanov and Kei Nishikori seek their first Australian Open title.

The 5 Players Who Can Challenge Djokovic, Nadal & Federer At The Australian Open

Find out who has the best chance of challenging the 'Big Three'

Alexander Zverev
There is no question that Zverev can compete against anyone on the ATP Tour. The manner in which the German captured the biggest title of his career at the 2018 Nitto ATP Finals — beating Roger Federer in the semi-finals and then Novak Djokovic in the final — proved that.

Zverev owns a combined 5-5 record against Federer (3-3) and Djokovic (2-2), with all five of those victories coming in the semi-finals or championship match of an event. And while the World No. 4 is winless against Rafael Nadal (0-5), Zverev has the tools to challenge the 2009 Australian Open champion should they meet in two weeks for the title. In fact, Zverev pushed eventual finalist Nadal to five sets two years ago in Melbourne at just 19 years old.

In 2018, Zverev led the ATP Tour with 58 tour-level match wins, and he has been victorious in eight of his past 12 clashes against Top 10 opponents. Add in the three-time Masters 1000 champion’s hunger for a maiden Grand Slam championship, and Zverev will be a serious threat to challenge the ‘Big Three’ in Australia.

Watch Zverev Beat Djokovic To Win The Nitto ATP Finals:

Kevin Anderson
Few players have been as consistent at the majors over the past two years as Anderson. The South African has reached the second week at six of his past seven Grand Slams. And while he lost in the opening round of last year’s Australian Open to Kyle Edmund in five sets, the current British No. 1 advanced to the semi-finals.

Federer and Nadal (three each) have reached the most Slam finals since the start of 2017, but Anderson (2017 US Open and 2018 Wimbledon), Djokovic and Cilic are tied for second with two major finals during that span. Anderson also continues to improve his big-match play: he earned his first three ATP Tour titles from 2011 through 2015, but has captured three trophies in the past 11 months.

While people may point to Anderson’s big serve and aggressive play from the baseline, it’s tough to ignore his grit on the court. In last year’s Wimbledon quarter-finals, Federer led Anderson two sets to none and would earn a match point in the third set. But Anderson battled back to not only beat Federer, but oust John Isner 26-24 in the fifth set of a marathon semi-final to break through to the final at SW19.

Marin Cilic
Cilic has proven that on his day, he can beat anyone in the world. The 2014 US Open champion has the all-around firepower — from his serve to his ground game — to take matters into his own hands against anyone who stands across the net from him. When the 18-time tour-level champion is confident in his game, even the best defenders in the sport struggle to neutralise his deep, flat strokes. He will also take confidence knowing that one year ago in Melbourne Park, he was on the doorstep of victory.

The Croat held two break points in the opening game of the fifth set in the 2018 Australian Open final against Federer before ultimately succumbing to the Swiss. So there’s no doubt that Cilic can put himself in position. The sixth seed is projected to have to go through Federer (QF), Nadal (SF) and Djokovic (F) in Melbourne this year, which would be a run of epic proportions.

So if Cilic does manage to lift his second major trophy, and he has to go through the ‘Big Three’ to do it, he will have certainly earned his hardware.

Karen Khachanov
Khachanov may be young at 22 years old, but the Russian has already proven that he is unafraid of competing against the best players in the world on the biggest stages in tennis. His power baseline game has drawn comparisons to compatriot and former World No. 1 Marat Safin.

Perhaps Khachanov’s biggest breakthrough came in a loss in the third round of last year’s US Open, where he lost a four-setter in four hours and 23 minutes against Nadal. Khachanov lost just six fewer points than the Spaniard in the match. And just two months later at the Rolex Paris Masters, he claimed his maiden ATP Masters 1000 title, defeating Djokovic in the final in straight sets.

“After some tough loses against top guys like Rafa in New York, I think they push me to the limit and even to work harder. And I saw that my level is there. I could play and compete on this level,” Khachanov said. “[I thought that] if I continue to do the same things what I was doing and the way I was playing with the guys like Rafa… against top guys, it would bring me [to that level] at one point and it will turn around on my side. So I was really believing in this, and actually that's what I've got.”

Khachanov will certainly be tested early and often in Melbourne, with a potential third-round meeting against Doha champion Roberto Bautista Agut and a fourth-round encounter against Cilic looming.

Watch Khachanov Stun Djokovic In Paris:

Kei Nishikori
Few players finished the 2018 season in sharper form than Nishikori. For a player who began the year on the ATP Challenger Tour — and losing his first match, no less — Nishikori managed to find the level that once carried him to No. 4 in the ATP Rankings, and quickly. Nishikori reached at least the quarter-finals of his final six tournaments of the year — not including the Nitto ATP Finals — before beating Roger Federer in round-robin play at The O2.

And if you thought the off-season would cool the 29-year-old’s momentum, Nishikori came out firing in Brisbane, winning his first tour-level title since Memphis in 2016. The World No. 9 owns nine victories against the Top 20 since the start of the US Open, and while he is seeded to meet Djokovic in the quarter-finals, and the Serbian leads their FedEx ATP Head2Head series 15-2, Nishikori’s confidence is sky-high.

This time last year, the Japanese superstar was not healthy enough to play the Australian Open. So wouldn't it be perfect if the culmination of his year-long journey ended with a deep run in Melbourne Park?