The first time Sergio Pettis’ accomplished brother Anthony took him into a mixed-martial-arts training session, the reserved Pettis was surprised by the differences.
Having trained in kickboxing and boxing, Sergio, six years younger, had been in gyms before. He had even grown up in a tough Milwaukee household with a strict mother who often sent her boys to bed by 8 p.m.
But this MMA stuff, it was wholly different.