This is mocking and drawing a parallel to an NBA basketball player by the same name that was greatly hyped coming out of college. Hill spent four years maturing his game in the pros before injuring himself and never completing a season injury free in six years. Hill spent a good portion of his prime b-ball years on benches nursing various injuries.
"Yeah, and management still loves her, she's Grant Hill."
"I would have been a STAR if it weren't for that knee injury."
"You can't Grant Hill your way out of the fact you always sucked."