The sudden, shocking retirement of Indianapolis Colts quarterback Andrew Luck has brought a lot of things into perspective. Injuries have been led to the abrupt end of many promising, often-time legendary NFL careers.
In commemoration of Luck's spectacular - some would argue Hall of Fame worthy - career, we're ranking the five most shocking retirements in NFL history.
Luck's retirement comes in at No. 1, but how does the rest of the list shake out?
Find out below:
5. D'Brickashaw Ferguson (32 years old)
A model of consistency on and off the field for a decade, the New York Jets left tackle missed just one snap his 10-year NFL career. The No. 4 overall pick out of Virginia in 2006, Ferguson played in 160 straight games and made three straight Pro Bowls. His blocking in the 2009 and 2010 seasons helped the Jets reach back-to-back AFC Championship Games.
But after the 2015 season, he abruptly called it quits, citing his declining ability as one of the main reasons. He could have fooled most of us though - the Jets had one of their best offensive seasons ever that year.
4. Calvin Johnson (30 years old)
"Megatron" was the No. 2 overall pick in the 2007 draft and endured a lot of bad seasons with the Lions. In his second pro season, the Lions went 0-16 and the team was in shambles. But upon hooking up with quarterback Matthew Stafford, Johnson began to emerge as one of the elite wide receivers.
With the speed of a much smaller man than one with his 6-foot-5 frame, and incredibly strong hands, he could dominate in double and even triple coverage.
In 2012, he broke the NFL record for receiving yards with a whopping 1,964 yards on a league-leading 122 catches.
Sadly, injuries reportedly caused him lingering pain throughout the final year of his career and in 2016 he retired.
3. Barry Sanders (31 years old)
Widely considered one of the two or three greatest halfbacks of all time, Sanders was just over a thousand yards shy of the NFL's all-time rushing record at the time of his retirement in 1999.
In ten years he made 10 Pro Bowls, and became only the third player to ever rush for over 2,000 yards in 1997. But despite being the workhorse back for the Detroit Lions, the team was rarely in contention for a deep playoff run - much less a Super Bowl.
Though Sanders has largely been vague for the past 20 years about why he retired, it's believed that he grew tired of chasing the NFL rushing record and losing in the playoffs constantly.
2. Jim Brown (29 years old)
Perhaps the greatest running back of all-time, Brown led the NFL in rushing eight times in nine NFL seasons. He was a three-time NFL MVP, and is the only player to average over 100 yards per game and over 5.0 yards per carry for a career.
But in 1965, despite never missing a game and coming off an NFL Championship appearance with the Cleveland Browns, he retired to pursue other interests. He would go on to star in movies and do sports commentary.
One can only imagine how high a bar he would have set for running backs had he played into his mid-30s.
1. Andrew Luck (29 years old)
Call it recency bias, but given the circumstances around him, Luck's retirement has absolutely stunned the football world.
Luck was the No. 1 overall pick in the 2012 NFL Draft and quickly made the Colts forget about Peyton Manning by delivering them three straight Pro Bowls and playoff appearances. But after the 2014 season, injuries began to mount.
He missed nine games in 2015 as well as the entire 2017 season. However, he emerged rejuvenated in 2018, throwing 39 touchdowns while completing a career-best 67-percent of his passes.
While injuries have certainly taken a toll on his perennial Pro Bowl career, Luck was coming off one of his best seasons ever, and the Colts were considered a Super Bowl contender for 2019.
But as he cited in his retirement speech, the numerous injuries he suffered have simply hurt his love of the game.
Few quarterbacks as good as Luck have retired as young as he has.
We wish him the best in his future endeavors but hope he's the last NFL superstar to have his career cut short like this.