St. Louis' first-round draft pick agreed to a contract on Saturday, but missed the first day of training camp so he could celebrate the birth of his first son.
The 6-foot-4, 265-pound defensive end then was placed on the non-football injury list Sunday, sidelined by right knee injury stemming from a workout in North Carolina two months ago.
"Robert came in with really a sprained knee from his workouts in North Carolina," St. Louis coach Steve Spagnuolo said after practice at Rams Park. "We thought he'd be better off over there with (trainer) Reggie (Scott). We really haven't seen Robert do anything. We want to get a good assessment where that knee is before we throw him out there with the rest of the guys."
Quinn worked with Scott on the tackle sleds and did other conditioning drills.
"I'm taking all the mental reps. That's all I can really do right now," Quinn said. "I'll make the most of the situation and keep a smile on my face. I just kind of tweaked it doing some D-line drills. The trainer said it's looking real good. The knee's going to be OK."
Quinn, the 14th pick out of North Carolina, had to wait five days after changing agents before signing his contract.
"It was just a business decision. I'm a football player," Quinn said. "It's just something I had to do. I've put it in the past and I'm moving on from there."
"With me, it's family first," Quinn said. "They allowed me to be there. As soon as he was born, I hopped on a plane and shot over here."
So, he became a millionaire and a father on the same day.
"I don't think too many people get to do that, so it's kind of a funny feeling," Quinn said.
Quinn had 11 sacks as a sophomore, but was among three players kicked off the team last year for receiving improper benefits, then was declared permanently ineligible.
He said he believes he will be on the field soon and working with his teammates.
Defensive coordinator Ken Flajole is anxious to see what Quinn can do.
"He's not going to learn it all in two weeks," Flajole said. "It's too much volume and the time is too short. If he can master something, maybe he goes in and maybe the first thing that he does is he can contribute on third down as he is learning how to play run defense on first and second downs.
"But his athleticism will help give him a chance to play right away, you know, contribute in some form or fashion."
Also Sunday, St. Louis and Jacob Bell finished restructuring the offensive guard's deal.
"We took our time and figured out what our best option would be," Bell said. "Certainly, I'm happy to be back. It's always tough. It's not what you want to ask a guy to do, but in order for us to be where we want to be, they have to bring in some extra talent and I had to negotiate a little bit."
"He's a good man," Spagnuolo said about Greco. "Hopefully, it'll work out for him."
Cornerback Marquis Johnson and fullback Brit Miller were placed on the physically unable to perform list, Spagnuolo said. Both players are rehabbing from knee injuries last season.
Copyright 2011 by The Associated Press