But the veteran lineman just felt it was time to step away. He didn't want to occupy a roster spot when his body wasn't giving him what he needed.
Looney had already fulfilled his dream of reaching the NFL and had a successful career. He played in 104 career games with 42 starts and stepped away from an opportunity where he had a chance to be New York's backup center.
The Giants signed Looney on Saturday to a minimum-salary contract to provide depth on the interior of their offensive line. He was on the field later that day.
Looney was in good spirits after practice Monday after having no problem with taking a lap alongside quarterback Daniel Jones after a botched snap.
"Yeah, you know, I love playing football," he said. "Football, I grew up with it, man. My family loves it. It's great to be here. I know Coach [offensive coordinator Jason] Garrett. He's a great guy. It's always exciting to work with a new team, so just very blessed to be here for this opportunity."
Looney is the third Giants player to call it quits since the start of camp. Kelvin Benjamin said he has had enough after being cut last week, and veteran linebacker Todd Davis retired Tuesday after just a few days with the team.