Isaiah Rodgers has been studying Xavier Rhodes for years. Now, he might have to replace him

Xavier Rhodes was jogging after a play and felt something pop. He dropped to the Lucas Oil Stadium turf and rolled over onto his back.

Yet another injury had struck the Colts' most veteran cornerback, this time in his hamstring. It came as they needed him, up 17-13 on Derek Carr and the Las Vegas Raiders.

But the Colts did not panic. Isaiah Rodgers was coming into the game.

That idea would have seemed far-fetched a couple of months ago. Rhodes is a three-time Pro Bowler who re-energized his career with the Colts last season. Rodgers was a sixth-round pick out of UMass who had 53 career defensive snaps entering the year.

But time moves quickly in a league called Not For Long, and people either move with it or get swept away. Rhodes has thrived for the past nine years at one of the game's most volatile positions, the past eight as a full-time starter.

Rodgers has started to do it by watching Rhodes.

"He's always telling me now that I'll end up being better than him," Rodgers said. "He's always telling me to keep working, keep working and keep working. I just go off what he says because he's been here for a long time, he's an All-Pro corner.

"I look up to him and listen to everything he tells me."

Rodgers has studied Rhodes for two years. He can list his accomplishments at random. It's all so he could be ready for a situation neither wanted to happen.

Rhodes did not return to Sunday's 23-20 loss to the Raiders, and he missed Wednesday's practice with the hamstring he could barely walk on after it popped. He's considered day-to-day as the Colts prepare for a win-and-get-in season finale Sunday at the Jacksonville Jaguars.

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For whenever he returns, a conversation has to happen about whether Rhodes can still be himself as the injuries pile up. He struggled through a calf injury that wouldn't seem to heal in the first half of the season. A week off took care of much of that, but six weeks later, he has another major lower-body issue to contend with at 31 years old.

Durability was Rhodes' calling card. His 6-foot-1 height and exceptional play at Florida State made him a first-round pick of the Minnesota Vikings back in 2013, but his ability to stay on the field turned that talent sustainable. Prior to this season, he'd played 120 of a possible 128 career games.

As he was fighting through the calf injury this season, safety Andrew Sendejo used to jokingly tell him to "suck it up."

"He doesn't get disgruntled over that," said Sendejo, who played seven years with Rhodes with the Vikings. "I know his personality. That's the kind of relationship we have. Obviously, it's tough to play through those things."

As the two 30-somethings joked, the youngest cornerback on the team would take notice of the results.

"He played a long time, and I always ask him, 'How did you do this?'" Rodgers said of Rhodes. "And with us adding an extra game, I asked him, 'No, really, how did you do this?'

"He's just telling me to take care of your body, to invest in your body, and it'll all just play out."

Rodgers' body is not the same as Rhodes', though. He's three inches and 34 pounds smaller. Coaches didn't used to let him play cornerback because they thought he was too small.

Rodgers grew up in Florida, where Rhodes starred for the state school, and cornerback was what he wanted to play, too. He went to UMass and used his receiver background to pull down 11 interceptions. His body was still underdeveloped, though, and the Colts took him in the sixth round last year to start as a kick returner.

His rookie year was like a redshirt season defensively. He spent defensive series watching Rhodes and Kenny Moore II and then watched them process games in the film room each week. They promised him his time was coming.

None of them knew how quickly it would arrive.

Rodgers started against the Baltimore Ravens and then against the Arizona Cardinals. Veteran quarterbacks have started to go after the young cornerback and he hasn't flinched, pulling down interceptions against Tom Brady and Derek Carr.

He's played 45% of the Colts' defensive snaps, but his three interceptions trail only Moore II and Darius Leonard for the team lead.

"Coming into the league this young, there’s some things you have to get past," Rhodes said. "I feel like he has gotten over those hurdles. I think he’s prepared himself to be able to become a starter."

If Rhodes' hamstring doesn't work, Rodgers' time to start could be now. That's not how they wanted this to come, but it's why they trade treatment and training tips all year long.

In the first-ever 17-game season, they're both trying to survive.

Contact Indianapolis Colts insider Nate Atkins at natkins@indystar.com. Follow him on Twitter @NateAtkins_.

This article originally appeared on Indianapolis Star: Colts: Isaiah Rodgers has studied Xavier Rhodes for years