Robert Downey Jr. Reads His Worst Reviews During Critics Choice Acceptance

Robert Downey Jr. won big at the Critics Choice Awards this weekend -- and to pay back the favor ... he rattled off some of the worst reviews he's received throughout his career.

The superstar went onstage Sunday to receive his statuette for Best Supporting Actor -- honoring his work in "Oppenheimer" -- and while he was going through his thank-you's ... he ended up acknowledging the group that was voting on that night's winners ... critics!

RDJ said he had a soft spot for this noble profession -- while also pointing out he'd received not-so-nice reviews from said critics over the years ... some of which he wanted to read.

It was hilarious ... Rob pulled out a list from his coat and started going through what he considers the nastiest and/or most humorous feedback he's gotten for his on-camera work since he's been in the biz. He didn't name any names, but the words spoke for themselves.

Just a few of the reviews that left a mark ... including a haiku of sorts that read "Sloppy, messy and lazy." The next one was more metaphoric, as he puts it ... "Like Pee-wee Herman emerging from a coma." Finally, one that stayed with him ... "Amusing as a bed-locked fart."

Again, Downey Jr. didn't elaborate on when these reviews were dished or for what movies/performances of his -- but we're sure a simple Google search can track 'em down.