Honestly what else is he going to do?
He doesn't have the reach to stay on the outside and GSP is fast so he'll eat shots all night if he doesn't close the distance. Let's be real here, GSP doesn't have tons of power and Hendricks can definitely eat quite a few of those jabs to get in and throw big shots.
I wouldn't expect anything less if Hendricks wants to put him away.
“Anna, my strong, terrifying Anna.” -Cas
"You lack the requisite spine and testicular fortitude to study under me" -Elodin