INDIANAPOLIS -- In a shocking development, Indianapolis Colts quarterback Andrew Luck announced his retirement from the NFL on Saturday night, saying constant injuries have taken away his love for the game.

Luck, who turns 30 on Sept. 12, had met with Colts owner Jim Irsay earlier to tell him of the decision.

The Colts played their third preseason game Saturday night in Indianapolis against the Chicago Bears. Luck already had been ruled out of the game due to an ankle injury, but he was seen on the sideline, laughing and conversing with teammates.

After the game, Luck announced the retirement decision during an impromptu news conference; he said an official announcement wasn't planned until Sunday afternoon but changed course once news broke during the preseason game.

"I've been stuck in this process," he said, stopping several times to overcome his emotions. "I haven't been able to life the live I want to live. It's taken the joy out of this game ... the only way forward for me is to remove myself from football."

Luck's early retirement ends what started as a promising career for the No. 1 overall pick in the 2012 draft. He led the Colts to the playoffs in each of his first three seasons in the NFL, including back-to-back AFC South titles and the AFC Championship Game in 2014.

But his career took a turn for the worse when he suffered a shoulder injury in Week 3 of the 2015 season. He has missed 26 games, including the entire 2017 season, due to shoulder, kidney and rib injuries. It was during the 2017 season while out that Luck questioned whether he would be able to continue his career.

But Luck returned in a big way last season.

He threw for 4,593 yards and 39 touchdowns to win NFL Comeback Player of the Year and lead the Colts back to the playoffs for the first time since 2015, showing he remained one of the top QBs in the league.

But injuries hit Luck again earlier this year when he suffered a calf strain that kept him out of the team's offseason activities and minicamp. Luck only participated in three days of training camp -- none as a full participant -- before it was announced that he was shutting it down because he had difficulty moving in the pocket.

Luck said on July 30 that he wouldn't return until he was 100 percent healthy, with part of the reason being he still had "emotional scars" from the 2017 season. After not being able to get a clear diagnosis of Luck's injury, Colts general manager Chris Ballard said two weeks ago that the QB was dealing with pain in the high ankle area.

Luck told reporters Saturday night that he first started thinking about retirement two weeks ago.

"I'm in pain; I'm still in pain," he said.

It's stunning news for a Colts team that went to the second round of the playoffs last season and in the eyes of many had a Super Bowl-caliber roster in 2019.

"It's very difficult," Luck said. "I love this team, I love my teammates."

Now, the Colts will turn to Jacoby Brissett, the 26-year-old quarterback acquired from the New England Patriots in 2017.

With Luck dealing with a variety of injuries in 2017, Brissett started 15 games for Indy, throwing for 3,098 yards, with 13 touchdowns and seven interceptions.

Sportsbooks reacted quickly to the Luck news, taking the point spread on the Colts' Week 1 road game at the Chargers off the board and lengthening Indianapolis' odds to win the Super Bowl.

The Colts had been 4-point underdogs to the Chargers. The SuperBook at Westgate Las Vegas moved Indianapolis' Super Bowl odds from 12-1 to 30-1.

Information from ESPN's David Purdum and Adam Schefter was used in this report.