Brad Pitt Dissed by Best Supporting Actress Winner Youn Yuh-jung

Brad Pitt's opportunity to announce an Oscar winner from a film he helped make ... turned into a bit of a diss on live TV ... courtesy of the Best Supporting Actress winner.

Yuh-Jung Youn won the category for her role in "Minari." We know, ya probably didn't see the film -- like many of this year's nominees -- but you'd have to believe Brad did ... because he produced it!!! However, Youn was clearly not impressed.

She gave Brad a shout-out that, whether intended it or not, played like a major diss. Youn said, "Mr. Brad Pitt, finally! Nice to meet you. Where were you when we were filming in Tulsa?"

The limited crowd at L.A.'s Union Station laughed at Youn's remark, perhaps thinking it was a playful flirtation ... and, who knows? Maybe it was an inside joke for the cast and Brad, one of their executive producers.

But, to the general Hollywood public, it seems like she was upset Brad wasn't more hands-on during filming. Anyway, Youn and Brad did get a chance to greet each other as she walked off stage. Check out the interaction ... seems like neither was too bent.