EUGENE, Ore. – Matthew Knight Arena hosted a one-of-a-kind event for 12,220 tennis fans for the NIKE Clash of the Champions Tuesday evening featuring tennis stars Roger Federer, Rafael Nadal, Maria Sharapova, Victoria Azarenka, and a surprise appearance from tennis legend John McEnroe.

“The NIKE Clash of the Champions is one of the most unique events we could dream of hosting,” University of Oregon Director of Athletics Rob Mullens told the media gathered to cover the event. “The collection of accomplished tennis greatness competing tonight is very special and we are honored to host each of these elite athletes.”

Federer owns a men’s record 16 Grand Slam singles titles, including the 2010 Australian Open, while Nadal counts the 2010 French Open, Wimbledon and U.S. Open among his nine career Slam titles. Sharapova brings the 2004 Wimbledon, 2006 U.S. Open and 2008 Australian Open titles to Eugene, while Azarenka is a five-time winner on the pro tennis tour, and was most recently a quarterfinalist at the 2011 Australian Open.

Tickets for the event sold out in less than an hour, and those who scooped up the precious ducats, weren’t disappointed when the four tennis stars stepped onto the court clad in Oregon-themed green and yellow uniforms and put on a world-class display.

Azarenka opened the evening with an impressive comeback against Sharapova. Three service breaks helped Azarenka erase an early 2-0 hole and she pulled away in the nine-point tiebreaker by winning in five-straight points for a 5-4 (5-0) win. The crowd was brought to its feet in the final game of the mixed doubles match, a 6-3 win for Federer and Sharapova, when guest chair umpire John McEnroe relieved Federer and drilled two winners on a front court drop volley and an emphatic overhand smash.

The exhibition reached its thrilling conclusion with another classic battle between the top two players in the world. Nadal fought off match point to hold serve in the 10th game and broke serve for the first time in the match. Nadal held serve once again the following game for a 7-5 win to cap the evening.

“This is the nicest arena I have ever played,” said Nadal.

“This was an incredible night for tennis,” said Federer.

“We are thankful and proud to share the stage tonight with long-time, partner Nike for a once-in-a-lifetime event hosting the world’s top tennis players,” said Mullens. “Tonight’s event, which sold out in minutes, speaks to the incredible love of tennis – and all sports – by fans in Oregon and it will no doubt deliver the joy Mr. Knight so eloquently wished for in the arena opening ceremonies.”

Fans were thrilled by the unannounced appearance of tennis legend John McEnroe, who served as the head official for the doubles match and entertained the audience with his mock tirades and verbal jabs with some of the top tennis players of this generation.

But the evening at the Matthew Knight Arena wasn’t just about great tennis or serious fun.

A portion of the proceeds will be donated to the players' foundations.