Not everyone in the National Football League goes on to play for many years. Some retirements happen to players when they're still in their prime. With some of them, it's because they wanted to go out on their own terms. Others were stuck in situations where they didn't see too much success and fell out of love with the game. And others dealt with the grueling aspect of football and chose to leave the game while they could still walk.

One year ago today, Andrew Luck added to the record books with one of the most shocking retirements in league history. He joined a rare group of players that chose to leave the game early for different reasons. All of them spanning different points in time. All of them, with a lot left that they could've done on the field.

Here's our list of the craziest.

Most Shocking NFL Retirements

5. QB Andrew Luck

As shocking as this recent news is, it doesn't yet match the same level as the others on this list. However, it's still shocking in its own right with how sudden the news came about.

andrew luck

Luck was coming off of a year in which he won 2018 Comeback Player of the Year and his fourth Pro Bowl season. His statistics were impressive, as he completed 430 of his 639 passes for 4,593 yards and 39 touchdowns to 15 interceptions. It was an incredible performance by the Stanford product that showed that he still had a lot left to show even after the torn labrum to his throwing shoulder that kept him out of the entire 2017 season.

Unfortunately, injuries played a major part in his career.

This long list of injuries would be the end of the 29-year-old as he announced his retirement on August 24, 2019. He drew the ire of Indianapolis fans who showered him with boos when he left the field. But with what he gave them during his time, they'll regret doing that. Especially with the numbers he put together during his time in the league.

The 2012 first overall pick may not make the Hall of Fame with his numbers. But it's still upsetting that fans couldn't see what he could've accomplished if the Colts organization tried to protect him more, and what he could've accomplished with a few more years of play.

4. LB Chris Borland

As shocking as Luck's retirement from the league was, it wasn't as bizarre as Borland after playing only one season in the NFL. In that season, he looked to be the future of not only the 49ers defense, but the future of the inside linebacker position.

He came away with 107 tackles (12 for a loss), one sack, one fumble recovery, and two interceptions. The former Wisconsin Badger was looking like a steal for San Francisco as he took over for an injured Patrick Willis in a significant way. But unfortunately, he chose to leave the game because of the fear of what concussions and their long-term effects are to the brain.

He has no regrets about leaving the NFL, and is doing research and helping players in the league right now in providing more safety and assistance.

“Ultimately, I’m very fortunate to have my health and different opportunities and I’ve settled into a place and I’ve embraced the role.”

It's uncertain what more he could've done in the league had he stayed, but he was named second runner-up for the Pro Football Focus Defensive Rookie of the Year Award, only trailing Aaron Donald and Khalil Mack.

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3. WR Calvin Johnson

Getting outside of the injury-related retirements, here is one of the players that left on their own terms. Here's the best receiver from the 2010 decade who left the league at the age of 30. Johnson left because of the lack of help that the Lions provided him during his time and no future hope of winning championships. Injuries played a part in it as well, but his time with Detroit ruined his love for the game.

And it's unfortunate too when looking at what he accomplished. Being drafted as the second overall pick, Johnson matched all of the expectations of being the best receiver in the league throughout his time.

Calvin Johnson, Falcons

Double-teams and even triple-teams were not successful against Johnson, as he retired with 11,619 yards in just nine seasons to go along with 731 catches and 83 of them going for touchdowns. His receiving yards in nine seasons were third-most by a receiver in their first nine seasons, trailing just Torry Holt and Jerry Rice. Since being drafted, no other receiver had more receiving yards, receiving touchdowns, or 100-yard games (46) than Johnson. His 5,137 receiving yards from 2011-2013 were the most in any three-season period.

Arguably his greatest feat is leading the league in receiving touchdowns in the Lions’ 0-16 season with the likes of Dan Orlovsky and Jon Kitna quarterbacking that team. That goes along with his single-season record of 1,964 receiving yards in 2012, six Pro Bowls, and four All-Pro selections.

2. RB Jim Brown

Brown retired on his own terms after having accomplished everything that an NFL player could accomplish. He's still considered the greatest player of all time to some, and it's no question as to why when looking at what he did during his time.

  • Pro Bowl and All-Pro honors in every year he played (nine each).
  • Four rushing triple crowns (1958, 1959, 1963, and 1965).
  • His single-season rushing yards record for the Browns is still not broken and is the longest standing single-season record out of any franchise.
  • He retired with the most rushing statistics in every major category (except yards per attempt which he placed second), including being one of the top in rushing yards all-time (11th; 12,312), rushing touchdowns all-time (sixth; 106), and total touchdowns all-time (10th; 126). He’s also still the all-time leader in rushing yards per game (104.3).
  • Three-time league MVP and won his NFL Championship in his final season.

Brown chose to leave because he was signed on to be in the movie The Dirty Dozen. Owner Art Modell gave an ultimatum that he could either be a football player or an actor. Brown chose the latter over the former.

It's uncertain what else he would've accomplished if he kept playing. But it's safe to assume that the numbers would've been too impressive to attempt to break.

1. RB Barry Sanders

Would it be anyone else? Anytime a surprise retirement happens, the first name that pops up is Sanders'. And it's easy to see why with what he did in the league before he left.

He’s the fourth-leading rusher in league history (15,269), 10th in rushing touchdowns (99), and seventh in yards from scrimmage (18,190). He also came away with two Offensive Player of the Year Awards, a 1997 NFL MVP, and 10 Pro Bowls and All-Pro selections each.

He put up at least 1,000 rushing yards in every season he was in the league, and to add to how outstanding he was as a back, when taking away his negative yard plays (which is believed to be 1,114) his career rushing average would be 6.3.

Much like Johnson, he left because of the Lions' organization, as he said in his book.

“The realization that management no longer cared about winning slammed me harder than any linebacker had ever hit me in my entire career. That realization trivialized everything I did during the off-season to prepare myself. It trivialized everything I dreamed about from the time I was a kid in Wichita.”

It was unfortunate to see him walk away when he still had so much to show. But, he ended his time in the league as a Hall of Famer and as arguably the best player in NFL history to retire early.