Nadal, Djokovic play in front of glacier

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)

So wacky.

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, there was Nadal and Federer’s infamous "Battle of the Surfaces" in Nadal’s native Mallorca in 2007:

(Jaime Reina/AFP/Getty Images)

And Nadal and Federer’s battle in the cramped confines of a New York street in 2006:

(Mike Ehrmann/WireImage/Getty Images)

And then there was Federer and Andre Agassi going at it on a full-size court on top of a helipad at the luxury Burj al-Arab hotel in Dubai in 2005:

(David Cannon for Dubai Duty Free/Getty Images)