2012 was a tremendous year for achievements in tennis as well as monumental upsets.
Each of the members of the Big Four experienced at least one such upset, and some of these came in crucial stages of Majors and ATP1000 tournaments.
Some tournaments were even famous for their recognizable performances by unknowns and underdogs.
Though the top players usually won the big tournaments, the finals were made more interesting by earlier defeats and inspired athletes.
Here are the top 25 upsets in men's tennis that occurred this past year.