Austin McBroom KOs Sparring Partner With Violent Uppercut In Training Sesh

Austin McBroom is clearly ready for his fight this weekend ... 'cause he flattened one of his sparring partners in a recent training sesh -- and the YouTuber's violent KO punch was all caught on video obtained by TMZ Sports.

McBroom, who's slated to finally box AnEsonGib at the Social Gloves 2 event at Banc of California Stadium on Saturday night, showed off his improving skills in a workout just days ahead of the huge fight night.

In the footage, you can see McBroom probing his opponent -- before dropping him with a vicious right hand to the jaw.

The force of the blow was so heavy, the dude immediately crumpled to the canvas -- and nearly spilled out of the ring in the process.

McBroom has showcased his quick hands before -- pummeling Bryce Hall in their fight back in 2021 -- but he's clearly taken things up a notch.

He and Gib have exchanged trash talk repeatedly over the last few months in the buildup to the fight -- and the guys nearly came to blows in the TMZ office last week. Seems McBroom is more than ready to settle things once and for all this week.