Andrew Luck's most vocal supporters aren't Indianapolis Colts fans — they're other players

Andrew Luck, a quarterback for the Indianapolis Colts, announced over the weekend that he was retiring from professional football at 29 years old, drawing reactions from just about every corner of the internet.

"This is not an easy decision," Luck said. "For the last four years or so I've been in this cycle of injury, pain, rehab, injury, pain, rehab. And it's been unceasing and unrelenting ... and the only way I see out is to no longer play football."

Injuries had kept Luck from playing in the preseason. Luck said the pain has taken away his joy for the game and he hasn't been able to live the life he wants to live. He played the 2016 season in pain, he said, and made a vow he wouldn't go down that road again.

According to Zac Keefer from The Athletic, Luck sustained the following injuries during six NFL seasons: torn cartilage in two ribs, a partially torn abdomen, a lacerated kidney that left him urinating blood, at least one concussion, a torn labrum and a calf/ankle injury.

Luck said Saturday that because he couldn't put his heart into the game, he would have been selling himself and his teammates short.

According to videos on social media and multiple reports from people at the game, there were some Indianapolis Colts fans who booed Luck as he exited Lucas Oil Stadium.

But while some fans may have booed the now-retired NFL player, his fellow athletes expressed nothing but support.

"It was terrible how the fans booed a man who gave them so much!!" Colts teammate Darius Leonard said on Twitter.

Eric Ebron also expressed nothing but support for his former teammate, saying "Andrew Luck will be somebody I tell my kids about."

Luck also got some love from people who aren't his teammates, including Richard Sherman, who plays for the San Francisco 49ers.

"This is a very rough game," Sherman wrote on Twitter. "Most people who have not played at this level will never understand what we put our bodies through season after season. We don’t need the sympathy because this is what we signed up for but to 'boo' a man that battled for that city is disgraceful."

Robert Griffin III, who plays for the Baltimore Ravens, showed support for his fellow quarterback, saying he is glad Luck "found peace" and that it was his decision alone to make.

Carlos Dunlap, a defensive end for the Cincinnati Bengals, also showed his support, even using the hashtag #HappyRetirement.

Support also came all the way from Texas ...

"An incredible competitor and a truly great person," JJ Watt tweeted. "I’ll miss competing against a guy who always played the game extremely hard, with an immense amount of respect. Wishing Andrew nothing but the absolute best moving forward. I know this had to be unbelievably difficult decision."

... from the East coast ...

"Let’s show respect & take our hats off for Andrew Luck," Jamal Adams of the New York Jets said. "We don’t know what he’s going through."

... and also the West coast.

"Andrew Luck, like many players, sacrificed his health in order to make money," Russel Okung, who plays for the Los Angeles Chargers, said. "Then he sacrificed money to recuperate his health. Congratulations to him!"

And it wasn't just current players showing support for Luck's decision. Other former NFL athletes chimed in, expressing their respect for Luck's decision to prioritize his health.

"I commend him for having the guts to come forward and be truthful," former NFL player Keith Bulluck said. "Personal health is more important than any game or team!"

But perhaps the most straightforward take came from Walter Jones, who retired from the NFL in 2010/

"Not many will understand your decision," Jones wrote on Twitter. "Though most haven’t been through what you’ve been through. In the end, your health, happiness and life is what matters most. Football is a business & one that throws you away at will. Andrew Luck, walk away proud, young man. You earned it."