Novak Djokovic and Rafael Nadal have added another chapter to the "crazy tennis exhibition match" file.
The world's top two players were in Argentina this week for the retirement festivities for David Nalbandian and found time to play their first ever matches against each other on the South American continent -- albeit matches that won't officially count.
The Friday match took place on a barge with Argentina's Perito Moreno Glacier serving as an unforgettable backdrop:
(Argentina's Ministry of Tourism/AP images)
It wasn't Nadal's first rodeo on a floating surface. He and Roger Federer squared off on a partially submerged court off the coast of Qatar in 2011 (only volleys, please):
(AFP photo/Qatar Open/Julien Crosner/Getty Images)
And in 2009, again in Qatar, he and Federer played on a tiny court atop a dhow, the traditional sailing vessel of the region:
(Julian Finne/Getty Images)
In other gimmicky exhibition match history, th...