Rafael Nadal
Rafael Nadal hasn't advanced beyond the quarterfinals in his last four Grand Slam tournaments. Reuters

The 2015 French Open got underway just two months ago, but the landscape of men’s tennis has seen a few significant changes since then. While most of the “Big Four” haven't seen their spot atop the sport change, Rafael Nadal is no longer ranked among the world’s top players with just the U.S. Open left on the 2015 Grand Slam schedule.

Heading into the second Grand Slam tournament of the year, Nadal was ranked seventh in the world. Because the “King of Clay” had been so dominant at the French Open, he was expected to make a deep run in the tournament and potentially improve his standing in the rankings. But Nadal was unable to outlast Novak Djokovic in the quarterfinals, and a subsequent second-round loss at Wimbledon has him ranked No.10 in the world.

Nadal’s loss at Wimbledon was surprising, but it wasn’t as shocking as it might have been a year ago. He was beaten in the first round of the AEGON Championships just prior to Wimbledon, and Nadal has failed to reach the quarterfinals in five tournaments this year.

While Nadal has taken the biggest fall of any player in the top 10, Stan Wawrinka has made the biggest leap. Having failed to advance beyond the quarterfinals in six tournaments after the Australian Open, Wawrinka ranked ninth in the world in May. But after upsetting the world’s No.1 player at Roland Garros, Wawrinka is now a top-four player in the sport.

Djokovic, Roger Federer and Andy Murray have held down the top three since April 6. Djokovic is the clear No.1, reaching the finals of each Grand Slam and only failing to win the French Open. His 13,845 points are more than 4,000 ahead of Federer in the rankings. There is more of a gap between the No.1 and No.2 players than there is between Federer and Kei Nishikori, who has been No.5 in the world since the start of the French Open.

Federer hasn’t won a Grand Slam since Wimbledon 2012, but he’s won four tournaments in 2015, while losing to Djokovic in the finals on three separate occasions. It has been an impressive showing for the Swiss star, who turns 34 on Aug. 8. He continues to chase his 18th Grand Slam.

Murray last won a Grand Slam at Wimbledon 2013, but advanced to the finals of the Australian Open and the semifinals of the French Open and Wimbledon this year.

Below is a look at the men’s rankings on the ATP World Tour prior to the start of the French Open, as well as what they look like now, after Wimbledon and heading into the U.S. Open.

May 25 Rankings July 20 Rankings

1) Novak Djokovic Novak Djokovic

2) Roger Federer Roger Federer

3) Andy Murray Andy Murray

4) Tomas Berdych Stan Wawrinka

5) Kei Nishikori Kei Nishikori

6) Milos Raonic Tomas Berdych

7) Rafael Nadal David Ferrer

8) David Ferrer Milos Raonic

9) Stan Wawrinka Marin Cilic

10) Marin Cilic Rafael Nadal