The notoriously indignant John McEnroe won 77 singles titles in his career, including seven Grand Slams. Together with doubles and mixed doubles titles, McEnroe won 17 Grand Slam tournaments. He recorded arguably the greatest season in tennis history in 1984, when he won 96.47 percent of his matches, including Wimbledon and U.S. Open titles. (Walter Iooss Jr.(3), Steve Powell(2), Manny Millan/SI)
GALLERY: Top 20 Athletes with Irish Connections

The notoriously indignant John McEnroe won 77 singles titles in his career, including seven Grand Slams. Together with doubles and mixed doubles titles, McEnroe won 17 Grand Slam tournaments. He recorded arguably the greatest season in tennis history in 1984, when he won 96.47 percent of his matches, including Wimbledon and U.S. Open titles. (Walter Iooss Jr.(3), Steve Powell(2), Manny Millan/SI)

GALLERY: Top 20 Athletes with Irish Connections

In the 33rd meeting between the two best players over the last 10 years, Rafael Nadal pulled out a 59-minute first set and rolled from there to improve to 3-0 against Roger Federer at the Australian Open, winning 7-6 (4), 6-3, 6-3 on Jan. 24, 2014.  As Rod Laver and Pete Sampras sat in the crowd, Nadal showed once again why his now 23-10 record against Federer is no fluke. (Rick Rycroft/AP)
GALLERY: Rafael Nadal vs. Roger Federer

In the 33rd meeting between the two best players over the last 10 years, Rafael Nadal pulled out a 59-minute first set and rolled from there to improve to 3-0 against Roger Federer at the Australian Open, winning 7-6 (4), 6-3, 6-3 on Jan. 24, 2014.  As Rod Laver and Pete Sampras sat in the crowd, Nadal showed once again why his now 23-10 record against Federer is no fluke. (Rick Rycroft/AP)

GALLERY: Rafael Nadal vs. Roger Federer

With his second U.S. Open victory in four years, Rafael Nadal has won 13 Grand Slam titles, passing Roy Emerson for third among the all-time leaders. His major victories include one Australian Open, eight French Opens, two Wimbledons, and two U.S. Opens.  (Heinz Kluetmeier(3), Bob Martin, David Callow, Darren Carroll/SI; Getty Images(5); EPA; AP)
GALLERY: Rafael Nadal’s Grand Slam Victories

With his second U.S. Open victory in four years, Rafael Nadal has won 13 Grand Slam titles, passing Roy Emerson for third among the all-time leaders. His major victories include one Australian Open, eight French Opens, two Wimbledons, and two U.S. Opens.  (Heinz Kluetmeier(3), Bob Martin, David Callow, Darren Carroll/SI; Getty Images(5); EPA; AP)

GALLERY: Rafael Nadal’s Grand Slam Victories