All you need to know about US Open champ Novak Djokovic

Factbox on Serbia's Novak Djokovic, who beat Swiss Roger Federer in the U.S. Open men's final on Sunday.

GRAND SLAM TITLES (10): Australian Open: 2008, 2011, 2012, 2013, 2015; Wimbledon: 2011, 2014, 2015; US Open: 2011, 2015 

Born: Belgrade, May 22, 1987

* Began playing tennis aged four. *  His father was a professional skier and wanted his son to be a skier or professional soccer player but changed his mind when Djokovic excelled at tennis from an early age. 

PLAYING CAREER 

First full year on tour in 2005: Made grand slam debut as a qualifier at the Australian Open, losing to Russian Marat Safin in the first round. Finished as the youngest player (18 years, five months) inside the top 100.

* In 2006, he won his first ATP tour title at Amersfoort.

* He retired in the 2006 French Open quarter-finals against Spaniard Rafael Nadal when trailing by two sets, and again a year later due to blisters in the Wimbledon semi-final against the same opponent. *In 2007, he won five titles (Adelaide, Miami, Estoril, Montreal and Vienna) and reached his first grand slam final at the U.S. Open, losing to Federer 7-6 7-6 6-4.

* Beat Frenchman Jo-Wilfried Tsonga in four sets to win his maiden grand slam title at the 2008 Australian Open.

* Failed to successfully defend his title in Melbourne the following year after controversially pulling out of his quarter-final against American Andy Roddick citing heat exhaustion on a sweltering day.

Related read: Novak Djokovic trounces Roger Federer to win second US Open title

* Led Serbia to their first Davis Cup title with victory over France in Belgrade in December 2010.

* Began 2011 by winning the Australian Open, beating Briton Andy Murray in the final, to end his three-year wait for a second grand slam title.

* Won his next six tournaments in Dubai, Indian Wells, Miami, Belgrade, Madrid and Rome. Did not lose again until June 3 when Federer ended his 41-match winning streak in the French Open semi-finals.

* Secured the number one spot on July 4 by beating Tsonga in the Wimbledon semi-finals, then beat Nadal to clinch his first Wimbledon crown, his first title on grass.

* Saved two match points to beat Federer in the semi-finals of the US Open then defeated Nadal in the final to become the seventh man to win three grand slam titles in a year since tennis turned professional in 1968.

* Won his third Australian Open title in 2012 by beating Nadal in five hours and 53 minutes.

* Defeated by Nadal in the 2012 French Open final. * Began 2013 by beating Murray to become the first man in the professional era to win three successive Australian Open titles.

* Loses to Nadal in the 2014 French Open final before beating Federer in a five-set Wimbledon final.

* Reached all four grand slam finals in 2015. Began the year by capturing a fifth Australian Open title, then missed out on the French Open again after falling to Stan Wawrinka in the final. Five weeks later draws level with his coach Boris Becker's Wimbledon haul of three titles by defeating Federer in the All England Club final. Beat Federer in US Open final, giving him three grand slam titles in a year for a second time.