Luck's most recent snap with the starting offense came in January. His litany of injuries led to his tearful retirement Saturday night, and created a mammoth hole behind center for the Colts.
''I'm in pain, I'm still in pain. It's been four years of this pain, rehab cycle,'' Luck said. ''It's a myriad of issues: calf strain, posterior ankle impingement, high ankle sprain. Part of my journey going forward will be figuring out how to feel better.''
Indy's journey forward will continue without its franchise quarterback, and the hope is Jacoby Brissett - who got plenty of experience in 2017 when Luck sat out - will step up.
He'll need to not only because he's now the No. 1 QB, but because of what's happened to the Colts this summer.
Adam Vinatieri, the NFL's career scoring leader, missed Indy's first two preseason games with an injured knee. All-Pro left guard Quenton Nelson missed all of last week with a sore ankle and starting defensive end Jabaal Sheard hasn't practiced since early August because of a problematic knee.
So far, the Colts have managed to adapt. But with the Sept. 8 season opener against the Los Angeles Chargers quickly approaching, coach Frank Reich needs answers.
Even with Luck gone, the Colts insist this season won't be a repeat of 2017 when they won four games and missed the playoffs for the third straight year. They believe in Brissett , who started 15 games that season, and they have a stronger supporting cast.
Two rookies, Nelson at left guard and Braden Smith at right tackle, coupled with the return of center Ryan Kelly and the emergence of right guard Mark Glowinski, helped one of the league's worst offensive lines in 2017 become a top-five line last season. With all five starters back, the group has a new goal: producing a top-five rushing offense.
So far, with Nelson and Kelly (shoulder) battling injuries and left tackle Anthony Castonzo taking extra days off, the line hasn't looked the same.
''We need to be better,'' Castonzo said after losing a preseason game at Buffalo. ''I think it's just going to come down to the fundamentals, getting back to doing the things you've been doing since you were 10 years old: hands inside, moving your feet and just playing better football.''
What does linebacker Darius Leonard do for an encore after leading the league in tackles and being chosen an All-Pro as a rookie?
Achieve higher goals.
''I wasn't named MVP, I wasn't a Super Bowl champion and I wasn't a Pro Bowler,'' Leonard said. ''So there are still goals I didn't reach last year.''
Leonard believes better fundamentals will help him reduce the number of missed tackles and hopes to create more turnovers.
Despite Sheard's injury, the Colts have beefed up their pass rush by singing 2014 NFL sacks champion Justin Houston.
The most notable change defensively might be a deep secondary, loaded with talent.
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