While they didn't walk the carpet together, the veteran actors stole the show on stage with an epic acceptance speech.
"I think it goes without saying that this is an award Matt and I have been dreaming about since we were little boys," Affleck began, joking of the pair's childhood growing up in Massachusetts. "I did Gigli and Matt did that Liberace movie, and all of a sudden, it all seemed out of reach. Then I did [Batman v Superman] and all of a sudden, it was back in reach again."
"Now we're the…coveted Dudes of the Decade...the Guys of the D---heads?" the father-of-three continued as the audience erupted in laughter.
"No, the D---heads of the Decade Award. What is it called?" Damon asked before finally getting it right. "It's the Guys of the Decade."
Although not a soul would dare question the authenticity of the Affleck/Damon friendship, what acceptance speech would be complete without a little smack talk about their other famous pals? "We will cherish this, and we want to recognize some of the other nominees," The Martian star stated. "Some of the dudes who weren't quite as decade-worthy: George Clooney and Brad Pitt."
"F--k you guys!" Affleck quipped.
The pair went on to mention several other dynamic duos, calling out James Franco and Jonah Hill, Leonardo DiCaprio and Tobey Maguire, Liam and Chris Hemsworth, Justin Bieber and Jaden Smith, and Ben and Jerry.
"We’re honored to share this fake award with all of you," Damon declared. "And after decades and decades of friendship, I want to thank my ultimate man of the decade--"
"Thank you," Affleck interrupted.
"I wasn’t talking to you," Damon snapped back, inciting one last roar from the crowd.
The Oscar winners concluded their time on the stage with a heartfelt thank you to the troops, who they also made time for during the event. An eyewitness tells ET that the actors were surrounded by service men and women throughout the night. Damon and Affleck sat by the troops during the show and were seen taking pictures and selfies during a commercial break.
The 2016 Guys' Choice Awards will air on Thursday, June 9 at 9 p.m. ET on Spike TV.
Almost 20 years after Affleck and Damon brought their bromance to the big screen in Good Will Hunting, Damon returned to MIT as commencement speaker for the class of 2016. Hear what he had to say in the video below.