It’s often said that men’s tennis is deeper and more competitive than it has ever been. And it’s true; the sport has never been played at a higher level. But over the last five years, it hasn’t been the excellence of the ATP as a whole that’s been most impressive. It has been the dominance of the top players despite that depth. Since 2006, we’ve seen three players—Roger Federer, Rafael Nadal and Novak Djokovic—put together seasons that rank among the most gloriously accomplished of the Open era.

Now that the third and perhaps finest of those seasons, Djokovic’s remarkable 2011, is complete, it seems like a good time to look back at where it—as well as Federer’s and Nadal’s best years—fits among the greatest single seasons of the Open era. There’s no right answer, and that’s what makes this parlor game so much fun. Here we present our countdown of the 10 best men’s seasons since the Open era began in 1968.

No. 9: John McEnroe, 1981

In his early years, McEnroe had been tennis’ temperamental teenage artist, a magician with a racquet who was one bad call away from self-destruction. In ’81, McEnroe, 21 and reaching his prime, showed the world exactly what he could do on a tennis court. It was as surprising as it was breathtaking. The former prep-schooler from Queens lost his baby fat at the start of the season; by its end, he had conquered the seemingly unconquerable Björn Borg. McEnroe ended the Swede’s five-year run at Wimbledon, took his No. 1 ranking, and drove him from the sport by playing circles around him at the U.S. Open. McEnroe capped the year with perhaps his proudest achievement: leading the United States to a dramatic win in the Davis Cup final over Argentina. As McEnroe said after the Open, that year he felt as if he could do anything he wanted with a racquet. Few did more with one than Johnny Mac in ’81.

Check TENNIS.com each day for the next season on the list.

Originally published in the Jan/Feb 2012 issue of TENNIS.