Matt Damon is a total slob, says former roommate Ben Affleck

They've shared a bank account and the silver screen, but one thing Ben Affleck will never share with Matt Damon again is an apartment.

Affleck said that his Good Will Hunting costar was such a messy roommate that it once pushed him and younger brother Casey Affleck to their breaking points when the trio shared an apartment together in Los Angeles.

"Matt's a beautiful guy. I love him. He's my best friend. He's been great to me my whole life. He's a brilliant guy," Affleck began on Thursday night's episode of The Late Late Show. "I would not suggest living with him."

He credited Damon with having the very unique ability to "block things out" entirely, even if, unfortunately, that also included "the idea that, when you finish with something, it has to be washed or thrown away."

After cleaning up his clutter "for years," Affleck said that he and Casey couldn't take it anymore and decided to go on a silent strike to see if Damon would realize the depths of his filth and start tidying up after himself. As Affleck put it, "We're just gonna wait and see how long he will go before he actually gets up and goes, 'God, I'm covered in garbage!'"

He said the pair made it "two weeks without touching the apartment" before Damon's Pigpen-like behavior caused them to snap.

"Came home one day, me and [Casey]. Matt's there in his shorts and his T-shirt playing the '92 Sega hockey game in the middle of what was the living room, just surrounded by concentric circles of garbage," he explained to host James Corden. "Pizza boxes. I look down at this sushi thing that was a week and a half old, and there's maggots."

"And we were like, 'We submit. We submit. You are too good. We cannot beat you,'" he continued. "He just was like, 'Hey what's going on fellas?' [We said,] 'That's a rat on you!'"

Affleck also gave a special shout out to Damon's wife, Luciana Barroso, who he has been married to for the last 18 years. "God bless his wife, Lucy," he concluded. "There's a place for you in heaven."

Watch Affleck discuss Damon being a horrible roommate in the clip above.

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