The Indianapolis Colts started their offseason program on Monday, kicking off Ryan Kelly’s fourth -- and possibly final -- year with the NFL team.

In 2019, Kelly will be playing on the final season of the four-year, $10.45 million contract he signed after the Colts selected him from Alabama with the 18th pick in the 2016 NFL Draft.

Indianapolis can lock up Kelly for another season by using its option for a fifth year on that contract. But the Colts must make that decision by May 3, and it comes with a hefty price tag.

If Indianapolis exercises its option for 2020, the Colts would pay Kelly the average salary of the offensive linemen with the third- through 25th-highest salaries in 2019, which should be close to $10 million. Kelly has a base salary of $1.875 million for 2019.

The 2020 money becomes guaranteed against injury as soon as Indianapolis uses the option and fully guaranteed when the NFL's business year begins in March.

If the Colts don't pick up their option or sign Kelly to an extension, he'll become an unrestricted free agent in March.

Kelly told reporters on Monday that he wasn't thinking about where his 2020 paycheck might be coming from.

“You don’t come into this league playing for contracts,” Kelly said. “Maybe initially that’s the way you’re thinking, and then you start getting into it, and you just want to be out there with your guys. … Last year was the most fun I’ve ever had playing football. I want to keep that rolling as much as I can, but at the end of the day, I have to do my job the best that I can do it and keep getting better every year. So that’s priority No. 1.”

In the Colts' first 38 games with Kelly on the team, Indianapolis posted a 13-25 record. Then the Colts won nine of their final 10 regular-season games in 2018, plus a playoff contest.

“I think for the most part we have a lot of guys back from what we had last year, so that’s reassuring,” Kelly said. “A lot of guys are here, ready to get to work. I’m excited. You can only train in the offseason for so long by yourself before you miss the guys, you miss the competitive atmosphere that you have here, so I think everybody’s excited to be back.”

The Colts re-signed right guard Mark Glowinski to a three-year, $16.2 million contract in January to keep their starting offensive line together for 2019. Kelly is flanked by Glowinski and Quenton Nelson, with Anthony Castonzo at left tackle and former Auburn standout Braden Smith at right tackle. Nelson and Smith came board last season in the first and second rounds, respectively, of the NFL Draft and earned spots on the All-Rookie team.

Indianapolis gave up 18 sacks in 2018, the fewest in the NFL even though only one team threw more passes than the Colts.

“Obviously, a big thing for me will be going throughout the year and trying to be healthy the entire year,” Kelly said. "When you can play with all five guys, it really makes a world of difference. Even just plugging one guy here and there, as much as you don’t think it’s going to make a difference, it really does.

"I think that's why it's such an important time now that we work out together, that we're doing things together -- eating dinner, lunch here and there. Hell, playing golf together, I guess. Just little things like that really make the season a hell of a lot more fun."

After starting every game during his rookie season, Kelly missed nine games in 2017 and four in 2018, although he was back for Indianapolis' two playoff contests.

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Mark Inabinett is a sports reporter for Alabama Media Group. Follow him on Twitter at @AMarkG1.