He was previously playing defensive end -- a position he's played his entire life -- but Haley said on Thursday that he "officially a meat and potatoes guy" and it doesn't appear that will change any time soon.
"The one thing I didn't want to do to Bobby is start this back and forth thing," Haley said. "I think that would be a detriment to him making it in the league."
Greenwood has a brother that plays offensive line and Haley calls his dad a "monster" and that he makes Bobby look small.
"He got some work last year [on the scout team]," Haley continued. "We coached him. He wasn't just on cards. You have to have a guy that understands some of the blocking schemes and some of the twists. That will be an advantage to him having played a lot of defensive line."
Haley says he made clear to Greenwood that, while things can change, the offensive line is probably his "best chance" to make the team.
"With coach [Bill] Muir his guy is a great o-line coach but a great developer of offensive line talent," Haley said. "Through some discussions, and maybe some circumstance, this subject came up again and we felt there's a chance."
Haley indicated that part of the reason for the switch was "circumstance" which could speak to a number of things: Ryan O'Callaghan's slight injury this week, the depth along the right side of the line or even Barry Richardson's injury last week.