Novak Djokovic is the defending men's singles champion at the French Open, but nine-time winner Rafael Nadal will begin this year's event as the clear favourite.

While world number one Andy Murray is struggling on clay, the likes of Dominic Thiem and Alexander Zverev looking in fine shape and it promises to be an intriguing battle in Paris.

With the help of Opta, we look at some of the key facts relating to the men's singles at Roland Garros.

- Rafael Nadal has won an astonishing nine French Open titles, three more than any other player in the Open era. Bjorn Borg sits second on the list.

- Three of the last five men's singles finals at Roland Garros have pitted the top two seeds against each other. Nadal beat Novak Djokovic in 2012 and 2014, while Djokovic got the better of Andy Murray in last year's showpiece.

- Only three players have won the tournament without losing a single set: Ilie Nastase (1973), Borg (1978 and 1980), and Nadal (2008 and 2010).

- The last time Djokovic failed to reach the final in two consecutive grand slams was in 2010. He was knocked out of this year's Australian Open in the second round by Denis Istomin.

- Andy Murray is hoping to become the first British player to win the French Open since Fred Perry in 1935. Four of Murray's last five defeats at Roland Garros have come at the hands of the world number one at the time, but he now holds that title.

- Three of the last six Roland Garros winners were ranked number one when they won the tournament, unlike any of the previous nine.

- Rising star Alexander Zverev, who beat Djokovic in the final of last week's Internazionali BNL d'Italia, has yet to beat a seeded player in a grand slam.

- Another in-form player, Dominic Thiem, has reached the last 16 in three of his last four grand slam appearances – including a run to the semi-finals at Roland Garros in 2016.

- Six of Nick Kyrgios' last nine grand slam defeats have been against either Murray or Richard Gasquet.

- Eighteen different players have won the French Open since it was last won by a French player (Yannick Noah in 1983).