So many of the NFL's brightest young stars are banking on 2018 as a comeback season after checking out early in 2017.
There's almost one Pro Bowl player from every position hoping to bounce back from a major injury or prolonged stretch on the sideline, including David Johnson, Odell Beckham Jr., Aaron Rodgers, J.J. Watt, Eric Berry, Greg Olsen, Joe Staley, and Jason Verrett.
The Colts told reporters Luck's rehab would last about six months, placing his projected return right around the start of training camp.
That never happened.
Not only did Luck miss the entire season, but concerns were also raised that his impairment would jeopardize the career of one of the NFL's most prolific young gunslingers.
Luck, the No. 1 overall pick in 2012, guided the Colts to 11-win seasons in each of his first three years, advancing to the AFC divisional round in his second year and the conference championship the following year.
But it's been downhill since. The shoulder and another injury cost him seven games in 2015 and likely impeded his 2016, in which the Colts finished 8-8 and missed the postseason for the second of three straight seasons.
Last year became a nightmare for the franchise, with Luck never appearing in a game despite the organization's tune from earlier in the year. The Colts won just four games, fired head coach Chuck Pagano, and restarted a head coaching search in February after Patriots offensive coordinator Josh McDaniels got cold feet and decided to stay in New England after accepting the job.
The Colts eventually hired former Eagles offensive coordinator Frank Reich, whose agent - Bob Lamonte - just happens to also represent Colts general manager Chris Ballard, making the hire seemingly convenient for the franchise after six other vacancies had been filled.
Reich, whose demeanor and quarterback pedigree should mesh well with Luck, might turn out to be an excellent hire, but the embarrassment of being left at the altar by McDaniels will haunt the Colts if Luck doesn't return to the form that made him one of the NFL's rising stars from 2012-2015.
The Colts are already well behind the eight ball, with the Titans and Jaguars usurping them over the past two seasons for AFC South supremacy, and the Texans building a formidable nucleus behind Deshaun Watson, Jadeveon Clowney, and, they hope, a healthy Watt.
The NFL could use another quarterback surge in the aftermath of a nightmarish 2017 season that saw Rodgers, the rookie Watson, Carson Wentz, and Carson Palmer each finish the season on injured reserve.
Although Wentz, Watson, and Jared Goff give the league some pizzazz at the game's most important position, Luck came out of Stanford as one the highest-rated quarterbacks in decades and appeared destined for superstardom until the injuries started piling up.
Conversely, several of the league's elite quarterbacks are on the downside of their careers. The ageless Tom Brady is still king, but his 2017 season was marred by a scathing ESPN report detailing friction between he and coach Bill Belichick and then a loss to Nick Foles and the Eagles in the Super Bowl.
Drew Brees brought the Saints back to the postseason but mainly played third fiddle behind the team's running game and defense. Last year was his first since 2009 that he didn't eclipse 4,500 passing yards. His 23 touchdown passes were his second-fewest in any season he's played at least 15 games.
Ben Roethlisberger, 35, still plays at a Pro Bowl level but keeps hinting at retirement. Eli Manning, a 36-year-old two-time Super Bowl MVP, has seen his passer rating drop in each of the last two seasons. Palmer retired, Alex Smith was traded from Kansas City to Washington, and Philip Rivers missed the playoffs for the fourth straight year.
The game thrives on elite quarterback play, and the NFL could really use Luck's re-emergence after ratings dipped and overall quarterback play last year declined.
The Colts have tried to build around Luck for the past two years, even as the shoulder injury has either hampered him or taken him off the field altogether.
Ballard has drafted four offensive linemen in his two seasons since becoming general manager, including Notre Dame's Quenton Nelson at No. 6 this past April. Some personnel believed Nelson and running back Saquon Barkley were the draft's two best overall prospects. Ballard also signed veteran guard Matt Slauson to bolster the line.
All that's left is for Luck to resume practicing and show signs that he'll be leading the Colts out of the tunnel for their season opener at Lucas Oil Field on Sept. 9 against the Bengals.
He started throwing footballs this week in front of media for the first time since last October. According to an NFL.com story, he didn't make strenuous throws and used a college ball, but reported no pain afterward.
For the first time in quite a while, there's optimism about Luck's ability to get back on the field.
Another setback would be disastrous for both the Colts and the NFL.
Geoff Mosher is an award-winning sports reporter, radio host, and TV personality with more than 20 years of experience covering all major sports and leagues. He also hosts regularly on 97.5 The Fanatic in Philadelphia and co-hosts "The Sports Shop" on Facebook.
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