Brent Hinds sings and plays guitar for the Grammy-nominated metal band, Mastodon. The band attended the Grammys and Hinds wore a full Los Angeles Dodgers uniform – specifically, #23. Now, since there is no 360-degree picture of Hinds entire look (like say, Nicki Minaj) we don’t know for certain that Hinds was dressed up as Kirk Gibson.
It would make more sense that he was wearing current Dodger Adrian Gonzalez’s jersey, but maybe he was planning on giving a Kirk Gibson fist-pump on his way to the stage if Mastodon had won Best Metal Performance instead of… Tenacious D? (Having heard none of the nominated songs, I have to say that sounds like a questionable decision.)
It should also be noted that in every picture of Hinds, he is giving the camera the middle finger. That’s so metal.