Not all the time, Marcelo didn't submit his first MMA opponent, and I wouldn't say his opponent was very good at MMA grappling.
Traven's way better a pure grappling than Frank Mir, but Traven got armbarred in their fight.
Granted, Jacare has way more fights and experience than those 2, but still, not all the time does a ADCC grappler beat a pure MMA grappler in an MMA setting once it hits the ground.
I totally agree here Damone, but personally I think Jacare has way more agressiveness than for instance Marcelo Garcia. Marcelo is awesome and all (he's my grappling idol), but he is (according to Ediie Bravo) like the worlds nicest guy whom I couldn't picture fight anybody with his fists or using violence at all. It's like he don't want to hurt his opponents, but MMA is a violent sport so he'll have to get a bit of the old hatin' in if he wants to win. Also a LOT of Marcelo's moves are tailor made for grappling not involving punching. A lot of grapplers have this problem, hell even Demian Maia showed us a lot of this in his fight against Herman.
Jacare, IMO, has both great MMA grappling and the aggressiveness chin to take a lickin' and keep on tickin'. He has the drive to hurt his opponent if his opponent hurts him.
But one could easily make the argument that Miller wins, of course.
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