US Open 2011: Roger Federer struggles to accept Novak Djokovic

Roger Federer was left stung by Novak Djokovic's comeback in their five-set US Open semi-final

5 instances when Novak Djokovic beat Roger Federer and Rafael Nadal in the same tournament

Who do you think is the most gracious and worst loser among Nadal, Federer, Djokovic and Serena Williams? - Quora

Novak Djokovic wins US Open 2015 final after beating Roger Federer

Novak Djokovic - Wikipedia

Novak Djokovic ties Roger Federer's hard courts Grand Slam record

Roger Federers tennissäsong 2011 – Wikipedia

Roger Federer: You can't always win, spc talk

Doing things the hard way made Djokovic tougher, says Pilic

Novak Djokovic - Wikiwand

Sport, Us/sport

2011 U.S. Open: Federer Is Set to Battle Djokovic in Semifinals - The New York Times

ATP Tour - Novak Djokovic beats Roger Federer 64 57 64 64 to win US Open Tennis Championships, his third major of the year and 10th of his career. How the match