He's called TJ, always takes part in the sprints(and loses).That was part of why it was interesting when Lucas accosts MC in the park, that Darryl and his track buddy (did he have a name?) are there also. Was it preplanned? It certainly seems like it as none look or act surprised to see the MC walking by. They both seem to be involved, as when they get off the bench they tell Lucas that he's taken it to far and they are leaving.
From that scene on, I had hope there'd be some "Intertwining" of the villains between Lucas, Darryl, and perhaps even Ethan/Zach.
It seems like Lucas was telling Darryl about the guy who grabbed Layla and the MC happened to walk in.
Darryl recognizes the MC and remembers Tori flirting with him, he backs off when Lucas starts his attack, like he expected to make some threats but not actual assault.