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Between Andrew Luck's contract and potential future earnings, Indianapolis Colts owner Jim Irsay estimates the quarterback is walking away from a half-billion dollars by retiring at age 29, per Mike Garafolo of NFL Network.

Irsay said, according to ESPN's Adam Schefter:

"It's a tough thing. Look it, he's leaving $450 million on the table potentially. I mean, a half a billion dollars, and he's saying, 'You know what, I want to have my integrity. I have to be able to look [wide receiver] T.Y. [Hilton] in the eye. Look my teammates, look Coach, look [GM] Chris [Ballard] and say, "I'm all in,"' and he just didn't feel he could do that."

Luck piled up more than $97.1 million in on-field earnings during his seven-year NFL career, per Spotrac. He had three years remaining on the six-year, $140 million deal he signed in June 2016. 

Schefter noted the Colts have reached a financial settlement with Luck and will not attempt to recoup any of the $24.8 million they would be allowed to collect back.

Had he played out his contract, he would have been eligible to sign a new one at age 32. That would have put him in line for at least one megadeal had he continued to perform at a high level.

Given that both the New England Patriots' Tom Brady and the New Orleans Saints' Drew Brees are playing into their 40s and have shown few signs of slowing, Luck is potentially walking away from more than a decade's worth of pay.

At the time Luck signed his lucrative extension in 2016, he was the highest-paid player in NFL history. His average annual salary of $23.3 million ranks 12th in the NFL, per Over the Cap. Five quarterbacks will make more than $30 million in 2019, with the Seattle Seahawks' Russell Wilson leading the way at $35 million.

The salaries will continue to rise as more players reset the market. In other words, Luck's next contract could have featured silly figures.

In the end, though, Luck decided the money wasn't worth the grind of being an NFL quarterback. Adam Schefter of ESPN reported the Colts star was "mentally worn down."

As Zak Keefer of The Athletic noted, the 6'4", 240-pound passer's body had been beat up through the years:

Luck had not played this preseason, as he dealt with a high-ankle issue.