Who has the most to prove at the US Open?

It’s the final Grand Slam of the tennis year, and there are myriad story lines — including which tennis stars on both the men’s and women’s draws have the most to prove. Rafael Nadal and Juan Martin Del Potro had great showings at the Olympic Games in Rio but hadn’t had great showings until their respective trips to Brazil. They’ll look to prove that they’ll be players to watch heading into 2017 but aren’t the key figures heading into the US Open.

For the women’s draw, Madison Keys has been consistent, firmly entrenched into the top 10, so her next level of evolution is to start winning major tournaments. Garbine Muguruza has been awfully quiet since her French Open win. She lost in the second round at Wimbledon and the third round in Rio. Her play in Cincinnati led her to a semifinal, and she’ll look to build on that in New York. 

These four have plenty to prove as the US Open begins today, but who has the most to prove over the next two weeks? Let’s get into it.

MEN’S DRAW

Novak Djokovic

Under normal circumstances, we wouldn’t need to discuss the best tennis player in the world when dissecting who has the most to prove, but he’s underperformed on the last two big tournaments this year: Wimbledon and the Olympics. He’s looked off his game, struggling against lesser opponents and not playing with the same consistency that allowed him to win 82 of his 88 matches and three slams last year.

He lost in the third round at Wimbledon to Sam Querrey, who played the best tennis of his career over the course of the two days their match lasted. At the Olympics, he lost in the first round to Juan Martin Del Potro, who also eliminated Rafael Nadal, who was playing very well leading up to their match.

If Djokovic can find his groove again, there isn’t a man on the tour who can beat him at his best right now, but after watching him falter in London and Rio, it’s only fair that we wonder just how long this slide will last.

Nick Kyrgios

Nick Kyrgios is the most divisive, fun, talented young, up-and-coming star on the tour right now. Much has been made about his potential marketability and how he might bring in more casual fans with Roger Federer entering the tail end of his career. None of these conversations are wrong. Kyrgios is flashy, explosive and has a style of play unique to today’s game. He has the height and power to serve with the best in the game and the instincts to become one of the best returners on tour — he just has to start winning. Or, more importantly, he has to care about winning.

In a New York Magazine feature last week, Kyrgios said he believed that he could win slams if he wanted, and if he wanted he’d train harder. However, he’s not sure what he wants. He’s apathetic, content with living in the 10th to 20th world ranking range. Everyone believes he has the talent to do big things, even Kyrgios himself, but it’s a matter of him wanting it bad enough — and maybe controlling his temper just a tad might help, too. 

Andy Murray

No one has had a better summer than Andy Murray. He reached the final at Roland Garros, succumbing to Novak Djokovic in four sets. He followed up a nice French Open run by winning Wimbledon for the second time and winning his second Olympic gold — the first time any man has done that in the single’s draw.

Heading into the US Open, no one has been hotter than Murray, who has won 22 of his last 23 matches. However, with everything good that Murray has done, he hasn’t had to go through Djokovic. He last beat Djokovic earlier this year in Rome leading up to the French Open, but the rivalry has been rather one-sided. Djokovic has won 71 percent of their matches and hasn’t lost consecutive matches to Murray since 2012. If Murray is to punctuate a fantastic 2016, he’s going to not only hope to see Djokovic in the final, but he’s going to have to beat him.

WOMEN’S DRAW

Monica Puig

When she’s at her best, like she was in Rio, Monica Puig moves around the court as well as anyone, pushes her opponents to the corners and unleashes devastating backhanded winners. She hasn’t always been her best at the slams and she’s never played past the fourth round, but after winning Olympic gold this summer, she’s as confident as she’s ever been.

She’s only 22, which means she’s only going to get better. She’s heading into the US Open unranked, but look for Puig to show that the run through Brazil wasn’t a fluke and that she deserves the attention she’ll receive in Flushing Meadows during the first week.

Angelique Kerber

Angelique Kerber began the year with a win over Serena Williams in the Aussie Open final. Since then? She’s continued to play fantastic tennis — so much so that she has an opportunity to leave New York with the world’s No. 1 ranking, a title that Serena Williams has held for 184 consecutive weeks.

Kerber had a disastrous clay court season as she lost in the first round of three consecutive tournaments, including the French Open, but she made the final in Rio (lost to Puig) and made the final in the Cincinnati lead-up to the US Open. She’s back to playing some of her best tennis, but she’s going to have to prove that she’s here to stay with a strong showing at the US Open. With a potential second slam and the world No. 1 on the line, we should expect her to do just that.

Serena Williams

Potentially losing the world No. 1 ranking is maybe somewhere between 20th and 200th on the list of concerns for Serena Williams heading into the US Open — historically her best major. Should Williams finish the fortnight with a win, she’ll move past Steffi Graf for the most Grand Slams in the Open Era with 23 and move past Chris Evert for the most US Open titles in the Open Era with her seventh.

Williams entered the 2015 US Open with an opportunity to complete the calendar slam and tie Graf at 22 but fell in the semifinals in a frustrating loss in which she seemed out of her element. In Rio, she lost in the third round but struggled in both the first and second rounds, looking sluggish and exhausted throughout the Olympics. Although there isn’t a question for many tennis observers, a record-setting 23rd slam could cement Williams as the greatest women’s tennis champion ever. And given her recent falters, she's out to prove she's both the best right now and the best ever.