Novak Djokovic has dethroned Roger Federer in many statistical categories yet there is one in which Federer still has an edge against the Serbian player.
Novak Djokovic is now the winningest tennis player at Roland Garros having won 23 grand slam trophies so far. He's the only male player to have won as many grand slam trophies - a record. Roger Federer is currently at 20 and he won't be getting any more as he retired from the sport last year however he still has the most grand slam match wins overall out of any player.
The Swiss maestro won 369 matches at grand slams in his career and that's the most so far. Djokovic is not that far behind with a really decent chance to take over but he'll need a few more great runs at grand slams; some of those might even come this year. He trails Federer by 21 wins as he currently sits at 348 wins which means that he won't be able to catch him this year.
Even if he wins both Wimbledon and the US Open, Djokovic will only end up at 369 which means he would be 7 matches short. He would complete the calendar grand slam which would be a tremendous consolation prize. In any case, Djokovic needs 21 more wins to replace Federer in that regard which would be either 3 grand slam wins or just a combined 21 wins over the course of the next few years. Time will tell whether Djokovic will get it but there is a good chance that he will be able to because he will be able to play a few more grand slams and certainly win a few matches.
He does have a better winning percentage already at 88.10 % compared to Roger's 86.01 %.