Eli Manning, 36, believes he can play another four years in the NFL.

"Yeah, I think sitting here right now, I think I can play another four years," the New York Giants quarterback said.

"That's the way the body feels. ... Again with football, you don't know what's going to be the difference, how you're going to feel next year. And right now I still have the same enthusiasm and I'm working hard and I like doing the training and watching film and doing everything ... I have to do to prepare for it. So I don't see it slowing down. I think until the time comes or that changes, I'm going to keep going as hard as I can."

Manning is under contract through the 2019 season and would turn 40 at the end of the 2020 campaign.

Giants general manager Jerry Reese said in January that the 14-year veteran and two-time Super Bowl champ is "probably on the back nine" of his career.