Jerzy Janowicz of Poland returns to Florian Mayer of Germany during their men's singles match on day five of the 2014 Australian Open tennis tournament in Melbourne on January 17, 2014. IMAGE RESTRICTED TO EDITORIAL USE - STRICTLY NO COMMERCIAL USE AFP PHOTO / WILLIAM WEST

Florian Mayer of Germany returns to Jerzy Janowicz of Poland during their men's singles match on day five of the 2014 Australian Open tennis tournament in Melbourne on January 17, 2014. IMAGE RESTRICTED TO EDITORIAL USE - STRICTLY NO COMMERCIAL USE AFP PHOTO / WILLIAM WEST

Jerzy Janowicz of Poland returns to Florian Mayer of Germany during their men's singles match on day five of the 2014 Australian Open tennis tournament in Melbourne on January 17, 2014. IMAGE RESTRICTED TO EDITORIAL USE - STRICTLY NO COMMERCIAL USE AFP PHOTO / WILLIAM WEST

Supporters of Jerzy Janowicz of Poland cheer during his match against Florian Mayer of Germany in their men's singles match on day five of the 2014 Australian Open tennis tournament in Melbourne on January 17, 2014. IMAGE RESTRICTED TO EDITORIAL USE - STRICTLY NO COMMERCIAL USE AFP PHOTO / WILLIAM WEST

Jerzy Janowicz of Poland throws his racquet in the air during his match against Florian Mayer of Germany in their men's singles match on day five of the 2014 Australian Open tennis tournament in Melbourne on January 17, 2014. IMAGE RESTRICTED TO EDITORIAL USE - STRICTLY NO COMMERCIAL USE AFP PHOTO / WILLIAM WEST

Florian Mayer of Germany returns to Jerzy Janowicz of Poland during their men's singles match on day five of the 2014 Australian Open tennis tournament in Melbourne on January 17, 2014. IMAGE RESTRICTED TO EDITORIAL USE - STRICTLY NO COMMERCIAL USE AFP PHOTO / WILLIAM WEST

Fans watch the match between Florian Mayer of Germany and Jerzy Janowicz of Poland during their men's singles match on day five of the 2014 Australian Open tennis tournament in Melbourne on January 17, 2014. IMAGE RESTRICTED TO EDITORIAL USE - STRICTLY NO COMMERCIAL USE AFP PHOTO / WILLIAM WEST

A doctor (L) speaks to Jerzy Janowicz of Poland during his match against Florian Mayer of Germany in their men's singles match on day five of the 2014 Australian Open tennis tournament in Melbourne on January 17, 2014. IMAGE RESTRICTED TO EDITORIAL USE - STRICTLY NO COMMERCIAL USE AFP PHOTO / WILLIAM WEST

Jerzy Janowicz of Poland returns to Florian Mayer of Germany during their men's singles match on day five of the 2014 Australian Open tennis tournament in Melbourne on January 17, 2014. IMAGE RESTRICTED TO EDITORIAL USE - STRICTLY NO COMMERCIAL USE AFP PHOTO / WILLIAM WEST

Jerzy Janowicz of Poland reacts during his match against Florian Mayer of Germany in their men's singles match on day five of the 2014 Australian Open tennis tournament in Melbourne on January 17, 2014. IMAGE RESTRICTED TO EDITORIAL USE - STRICTLY NO COMMERCIAL USE AFP PHOTO / WILLIAM WEST

Jerzy Janowicz of Poland throws his racquet in the air during his match against Florian Mayer of Germany in their men's singles match on day five of the 2014 Australian Open tennis tournament in Melbourne on January 17, 2014. IMAGE RESTRICTED TO EDITORIAL USE - STRICTLY NO COMMERCIAL USE AFP PHOTO / WILLIAM WEST

Jerzy Janowicz of Poland returns to Florian Mayer of Germany during their men's singles match on day five of the 2014 Australian Open tennis tournament in Melbourne on January 17, 2014. IMAGE RESTRICTED TO EDITORIAL USE - STRICTLY NO COMMERCIAL USE AFP PHOTO / WILLIAM WEST

A fan strikes a pose while watching Jerzy Janowicz of Poland playing Florian Mayer of Germany during their men's singles match on day five of the 2014 Australian Open tennis tournament in Melbourne on January 17, 2014. IMAGE RESTRICTED TO EDITORIAL USE - STRICTLY NO COMMERCIAL USE AFP PHOTO / WILLIAM WEST

Jerzy Janowicz of Poland returns to Florian Mayer of Germany during their men's singles match on day five of the 2014 Australian Open tennis tournament in Melbourne on January 17, 2014. IMAGE RESTRICTED TO EDITORIAL USE - STRICTLY NO COMMERCIAL USE AFP PHOTO / WILLIAM WEST

Jerzy Janowicz of Poland returns to Florian Mayer of Germany during their men's singles match on day five of the 2014 Australian Open tennis tournament in Melbourne on January 17, 2014. IMAGE RESTRICTED TO EDITORIAL USE - STRICTLY NO COMMERCIAL USE AFP PHOTO / WILLIAM WEST

Jerzy Janowicz of Poland returns to Florian Mayer of Germany during their men's singles match on day five of the 2014 Australian Open tennis tournament in Melbourne on January 17, 2014. IMAGE RESTRICTED TO EDITORIAL USE - STRICTLY NO COMMERCIAL USE AFP PHOTO / WILLIAM WEST

Florian Mayer of Germany makes a backhand return to Jerzy Janowicz of Poland during their third round match at the Australian Open tennis championship in Melbourne, Australia, Friday, Jan. 17, 2014. (AP Photo/Shuji Kajiyama)

Florian Mayer of Germany serves to Jerzy Janowicz of Poland during their third round match at the Australian Open tennis championship in Melbourne, Australia, Friday, Jan. 17, 2014. (AP Photo/Shuji Kajiyama)

Jerzy Janowicz of Poland pours water over himself during his third round loss to Florian Mayer of Germany at the Australian Open tennis championship in Melbourne, Australia, Friday, Jan. 17, 2014.(AP Photo/Aijaz Rahi)

Florian Mayer of Germany waves to the crowd after defeating Jerzy Janowicz of Poland in their third round match at the Australian Open tennis championship in Melbourne, Australia, Friday, Jan. 17, 2014.(AP Photo/Aijaz Rahi)