Yankees fans in the outfield threw thrash at the Cleveland players after the Yankees walk-off win.

The tension began after Isiah Kiner-Falefa hit a double to left to tie the score in the ninth inning. Left fielder Steven Kwan had gone down with an injury that he incurred while banging into the wall on the play. Straw climbed up the left field wall to confront a fan after that play.

NYPost.com

It seems the fans were being a bit nasty about Kwan getting injured. Aaron Judge and Giancarlo Stanton took it upon themselves to guard the Guardians:

The ugly scene resulted in Aaron Judge and Giancarlo Stanton, among other Yankees, taking a break from celebrating the 5-4 victory to try calming things down.

I would not be surprised if those fans are disciplined, or at least banned from the ballpark for a while.