Quarterbacks use their hands, too, of course. It is just that one hand — their throwing one — is more important. Fitzpatrick receives snaps, hands off the ball and scrambles, all without noticing he is wearing the ring. It is not so easy for someone like Jim Leonhard, a Jets safety who used to wear his ring to practice.

Image The ring fits snugly on Ryan Fitzpatrick's exposed left ring finger, and in two seasons it has yet to fall off or even come loose. Credit... David Duprey/Associated Press

“There were a couple times when I jammed a finger, and I couldn’t get it off for three or four days,” Leonhard said. “It scared me more than anything. You hear horror stories in the working world of having to get your ring cut off, and I wanted no part of that.”

Fitzpatrick was not married when he made his N.F.L. debut in 2005, with the Rams. But he planned to propose soon to Liza Barber, whom he met at Harvard. On the same day he purchased her engagement ring with money from their shared bank account, a cashier at the Gap thought Barber had been double-charged for an item. When Barber said that she would check her bank balance later, Fitzpatrick, with the ring hidden in his car, knew he had to propose before they got home.

Barber told him she craved McDonald’s. The first one they spotted was attached to a gas station.

“I asked her when she was between her third and fourth Chicken McNugget,” Fitzpatrick said. “She had sweet and sour all over her face.”

Tampa Bay’s quarterbacks coach, Alex Van Pelt, who was Fitzpatrick’s offensive coordinator in Buffalo in 2009, said he was not surprised about the ring.

“He’s just a loyal family guy, there’s no question,” Van Pelt said.

Given that the N.F.L. seems to levy fines at the drop of a helmet for the slightest uniform infraction, it may be somewhat surprising that Fitzpatrick is permitted to wear the ring at all. But wearing jewelry constitutes an escape from conformity. League policy prohibits only “metal or other hard objects that project from a player’s uniform, including from his shoes.”

For a while after Fitzpatrick was married on June 24, 2006, he would fiddle with his ring, telling himself how strange it felt. It was not until training camp last year that Fitzpatrick thought about playing with the ring on. He did not consult Liza.