A heated Brooks Koepka is annoyed at Bryson DeChambeau in previously unaired video

What Phil Mickelson did in winning the PGA Championship at age 50 this past weekend was incredible. 

But this new, previously unaired video of Brooks Koepka dropping a bunch of curse words and looking very annoyed at Bryson DeChambeau during a post-round interview at Kiawah Island is also incredible.

Koepka and DeChambeau haven't liked each other for a while, but this video takes things to a whole new level. Koepka was being interviewed about his round (it looks like after Friday's second round) by Golf Channel's Todd Lewis when DeChambeau walked behind him.

WARNING: Language

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Koepka was actually annoyed just seeing DeChambeau near him at the start of the interview, and it got worse when DeChambeau appeared to say something.

They had to cut the interview. Koepka said, "I honestly wouldn't care" if the video got out.