#2 Masters 1000s
Djokovic is the undisputed winner in this category, winning 29 Masters 1000 titles from 39 finals during the 2010s decade. Federer in the 2000s won 16 Masters 1000 titles from 25 finals.
The Serb reached eight Masters 1000 finals in 2015, winning six, which are respective records for most Masters 1000 finals and titles in a calendar year.
With 263 Masters 1000 match wins during the decade to go with 47 defeats (84.8%), Djokovic's match win rate in this category during the 2010s comfortably outscores that of Federer's corresponding 2000s tally of 202 wins and 59 losses (77.3%).
WINNER: Djokovic of the 2010s
#3 ATP Finals
Federer during the 2000s registered a 29-7 match win-loss record (80.6%) at the ATP Finals, winning titles in 2003-04 and 2006-07, while losing his sole title match in 2005 to David Nalbandian. That loss to the Argentine prevented the Swiss maestro from tying John McEnroe's record for the best match-win loss record in a season (82-3).
Djokovic during the 2010s registered a 30-9 match win-loss record (76.9%) at the season-ending tournament, becoming the first player in the history of the ATP Finals to win four consecutive editions (2012-2015). However, he lost title matches in 2016 to Andy Murray and in 2018 to Sascha Zverev.
With both players winning an identical tally of four titles at the ATP Finals during the two decades, Federer of the 2000s takes the honours in this category owing to a better match wins record compared to that of the Serb.
WINNER: Federer of the 2000s
#4 All titles
After reverses in his first two singles finals (), Federer picked up his first career singles title on the carpet of Milan in 2001. After a record 24-match unbeaten run in finals from 2003 Vienna to 2005 Bangkok, David Nalbandian fought back from two sets down and then a break down in the fifth to end Federer's stunning run in tournament title matches.
Federer did not lose a final in the entire 2004 season. He racked up impressive title hauls of 11, 11, and 12 in 2004, 2005 and 2006 respectively, going on to win a total of 61 titles from 85 finals (72.9% finals record) in the 2000s decade.
Djokovic put up equally staggering numbers in the 2010s decade, winning an identical 61 titles but from just one fewer final than Federer played in the 2000s, at a marginally superior win rate of 73% (61-23) in tournament finals.
The Serb won 10 or more titles in a season on two occasions during the 2010s, bagging 10 titles in 2011 and 11 in 2015. However, Djokovic in the 2010s, unlike Federer in the 2000s, did not manage any season during the decade without losing a tour-level final.
That, coupled with the fact that Federer reached one more final than Djokovic, is the reason why Federer of the 2000s should be considered a slightly more dominant player in the decade than Djokovic was in the 2010s.
WINNER: Federer of the 2000s
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