Logan Paul ain't the only Paul whoopin' ass in the ring ...
Here's little bro Jake Paul beating the snot out of one his sparring partners ahead of his huge fight with KSI's little bro, Deji, on August 25.
Paul hits him with a few body shots, then a few head shots, and finishes him in a tangled mess in the ropes.
You can see Jake's big bro, Logan, watching the session from outside the ring -- and loving it.
A couple of guys who were at the house rushed over to help the sparring partner.