Matt Damon and Ben Affleck have had each other's backs for 37 years. That said, you know Matt probably did have some smaht remarks about Ben's back tattoo, he just saved them for Ben's ears only.

Matt Damon was just on "The Daily Show With Trevor Noah" for a serious reason -- promoting Water.org and WaterEquity with co-founder Gary White, to talk about their efforts to help millions of people in developing countries gain access to safe water. There's a global water crisis happening around the world.

But it has to wait a minute, because Trevor Noah had to start the interview with more "pressing news first."

Here's that part of the conversation:

Trevor Noah: "When did you break up with Ben Affleck? When did that friendship end? Are you guys not friends anymore?"

Matt Damon: "Unfortunately, I can't seem to shake him. No, I've known him since I was 10, so it's [been] 37 years."

Trevor: "You guys are still friends?"

Matt: "Unfortunatley, yes."

Trevor: "You say that, but I don't believe a friend would allow a friend to get a back tattoo of a colorful dragon. Have you see this tattoo?"

Matt: "Of course. It's not one man's job to tell another man what he can do to his back. You know, I support him in all of his artistic expression."

[Matt and the audience all laughed.]

Trevor: "Fair enough. That's a good friend answer, actually."

That is the good friend answer, especially in a public forum. In private, he's probably giving Ben crap -- unless he figures Batfleck has taken enough crap this past year.

Ben first showed off his phoenix rising from the ashes tat on the set of "Live by Night." At the time, he had said it was fake for a movie, but now it appears to be forever. Either way, it's his body, his choice, his life. He can keep it.

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