A tweet from UFC star Conor McGregor Tuesday saying he "decided to retire young" sent shockwaves through the mixed martial arts world and social media. But in a Facebook post Thursday, he stated, "I AM NOT RETIRED." While McGregor -- who's 27 -- may not be ready to leave the octagon, here are some other athletes who called it quits early in their careers.
Conor McGregor —
A tweet from UFC star Conor McGregor Tuesday saying he "decided to retire young" sent shockwaves through the mixed martial arts world and social media. But in a Facebook post Thursday, he stated, "I AM NOT RETIRED." While McGregor -- who's 27 -- may not be ready to leave the octagon, here are some other athletes who called it quits early in their careers.
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With no fanfare or farewell press conference, Detroit Lions wide receiver Calvin Johnson retired from the NFL in March at age 30 after nine seasons. "Let me assure you that this was not an easy or hasty decision," Johnson said in a statement. "As I stated, I, along with those closest to me, have put a lot of time, deliberation and prayer into this decision and I truly am at peace with it."
Calvin Johnson —
With no fanfare or farewell press conference, Detroit Lions wide receiver Calvin Johnson retired from the NFL in March at age 30 after nine seasons. "Let me assure you that this was not an easy or hasty decision," Johnson said in a statement. "As I stated, I, along with those closest to me, have put a lot of time, deliberation and prayer into this decision and I truly am at peace with it."
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Chicago White Sox designated hitter Adam LaRoche abruptly retired during spring training when the organization told him his his son Drake couldn't be in the clubhouse as often as he was last season, which the White Sox said was "100%" of the time. LaRoche, 36, left a reported $13 million on the table by retiring.
Adam LaRoche —
Chicago White Sox designated hitter Adam LaRoche abruptly retired during spring training when the organization told him his his son Drake couldn't be in the clubhouse as often as he was last season, which the White Sox said was "100%" of the time. LaRoche, 36, left a reported $13 million on the table by retiring.
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San Francisco 49ers inside linebacker Chris Borland retired in 2015 at age 24. He told ESPN's "Outside the Lines" that he was retiring because he was worried about the long-term effects of repetitive head trauma. Borland is one of several NFL players recently to cite health concerns as a reason to walk away from the game.
Chris Borland —
San Francisco 49ers inside linebacker Chris Borland retired in 2015 at age 24. He told ESPN's "Outside the Lines" that he was retiring because he was worried about the long-term effects of repetitive head trauma. Borland is one of several NFL players recently to cite health concerns as a reason to walk away from the game.
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Women's tennis star and then-world No. 1 Justine Henin announced her retirement to the press on May 14, 2008, in Limelette, Belgium, at age 25. "It's the end of a wonderful adventure, but it's something I have been thinking about for a long time," Henin said. Henin, who won seven Grand Slam singles titles, returned to the WTA in 2010 before retiring for good in 2011.
Justine Henin —
Women's tennis star and then-world No. 1 Justine Henin announced her retirement to the press on May 14, 2008, in Limelette, Belgium, at age 25. "It's the end of a wonderful adventure, but it's something I have been thinking about for a long time," Henin said. Henin, who won seven Grand Slam singles titles, returned to the WTA in 2010 before retiring for good in 2011.
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Running back Ricky Williams, who was then with the Miami Dolphins, announced his retirement in 2004 at age 27. At the time, it was believed Williams left because of personal issues, including a failed drug test. However, Williams later said it was because the Dolphins had bad quarterbacks in A.J. Feeley and Jay Fiedler. He returned to the NFL in 2005 and retired for good in 2012.
Ricky Williams —
Running back Ricky Williams, who was then with the Miami Dolphins, announced his retirement in 2004 at age 27. At the time, it was believed Williams left because of personal issues, including a failed drug test. However, Williams later said it was because the Dolphins had bad quarterbacks in A.J. Feeley and Jay Fiedler. He returned to the NFL in 2005 and retired for good in 2012.
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Detroit Lions running back Barry Sanders stunned the sports world when he announced his retirement from the NFL at age 31. He was 1,457 yards short of Walter Payton's career rushing record of 16,726, which was then the all-time record. Sanders, who was inducted into the Pro Football Hall of Fame in 2004, is now third on the all-time rushing list.
Barry Sanders —
Detroit Lions running back Barry Sanders stunned the sports world when he announced his retirement from the NFL at age 31. He was 1,457 yards short of Walter Payton's career rushing record of 16,726, which was then the all-time record. Sanders, who was inducted into the Pro Football Hall of Fame in 2004, is now third on the all-time rushing list.
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On May 11, 1994, Detroit Pistons' captain Isiah Thomas, then 32, announced his retirement from basketball at the Palace of Auburn Hills in Detroit. Thomas played 13 years and won two NBA championships, all with the Pistons.
Isiah Thomas —
On May 11, 1994, Detroit Pistons' captain Isiah Thomas, then 32, announced his retirement from basketball at the Palace of Auburn Hills in Detroit. Thomas played 13 years and won two NBA championships, all with the Pistons.
MICHAEL E. SAMOJEDEN/AFP/Getty Images
Chicago Bulls basketball star Michael Jordan shockingly announced his retirement on October 6, 1993, his first retirement from the game of basketball. Jordan, who was 30, said he "had reached the pinnacle of his career" and had nothing else to prove. Jordan went on to play minor league baseball in the Chicago White Sox organization before returning to the NBA in 1995 with a simple fax to media outlets that said, "I'm back." He retired again from the Bulls in 1999 and then retired for the third and final time in 2003 from the Washington Wizards.
Michael Jordan —
Chicago Bulls basketball star Michael Jordan shockingly announced his retirement on October 6, 1993, his first retirement from the game of basketball. Jordan, who was 30, said he "had reached the pinnacle of his career" and had nothing else to prove. Jordan went on to play minor league baseball in the Chicago White Sox organization before returning to the NBA in 1995 with a simple fax to media outlets that said, "I'm back." He retired again from the Bulls in 1999 and then retired for the third and final time in 2003 from the Washington Wizards.
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Magic Johnson, seen here hugging guard Isiah Thomas before the 42nd All Star Game at Orlando Arena in 1992, announced November 7, 1991, that he was retiring from the NBA at age 32 after contracting HIV. That 1992 All-Star Game was the first game of the season for Johnson after his retirement. He also was part of the 1992 "Dream Team" that won gold in the Summer Olympics in Barcelona. Johnson briefly returned to the NBA during the 1996 season but retired permanently after that, at age 36.
Magic Johnson —
Magic Johnson, seen here hugging guard Isiah Thomas before the 42nd All Star Game at Orlando Arena in 1992, announced November 7, 1991, that he was retiring from the NBA at age 32 after contracting HIV. That 1992 All-Star Game was the first game of the season for Johnson after his retirement. He also was part of the 1992 "Dream Team" that won gold in the Summer Olympics in Barcelona. Johnson briefly returned to the NBA during the 1996 season but retired permanently after that, at age 36.
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Bo Jackson, a dual-sport superstar in the NFL and MLB, had his career cut short by a devastating hip injury. As a running back for the Los Angeles Raiders, Jackson, then 28, suffered the injury during a game in 1991, which ultimately would be the last game in his NFL career. After hip surgery, Jackson was able to return to baseball. He retired after the 1994 season.
Bo Jackson —
Bo Jackson, a dual-sport superstar in the NFL and MLB, had his career cut short by a devastating hip injury. As a running back for the Los Angeles Raiders, Jackson, then 28, suffered the injury during a game in 1991, which ultimately would be the last game in his NFL career. After hip surgery, Jackson was able to return to baseball. He retired after the 1994 season.
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Tennis legend Bjorn Borg of Sweden, seen here kissing the Wimbledon men's singles trophy after winning it for the fifth time, retired at age 26 in 1983, shocking the tennis community. Borg won 11 Grand Slam titles. He attempted a comeback in 1991, but it was short-lived, because he was unfit and still using a wooden racket.
Bjorn Borg —
Tennis legend Bjorn Borg of Sweden, seen here kissing the Wimbledon men's singles trophy after winning it for the fifth time, retired at age 26 in 1983, shocking the tennis community. Borg won 11 Grand Slam titles. He attempted a comeback in 1991, but it was short-lived, because he was unfit and still using a wooden racket.
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Running back Gale Sayers, pictured here in 1972, had just retired from the Chicago Bears at age 29. Sayers was plagued by injuries, tearing ligaments in his right knee in 1968 and then the left knee in 1970. He tried a comeback in 1971 and 1972 before hanging the cleats up for good.
Gale Sayers —
Running back Gale Sayers, pictured here in 1972, had just retired from the Chicago Bears at age 29. Sayers was plagued by injuries, tearing ligaments in his right knee in 1968 and then the left knee in 1970. He tried a comeback in 1971 and 1972 before hanging the cleats up for good.
AP
Cleveland fullback Jim Brown, seen here reading a story about himself in the New York Daily News in 1965, retired from the NFL in 1966 at age 30. Brown played for the Cleveland Browns for nine seasons, winning the NFL championship in 1964, the last year the city of Cleveland won a major championship. Brown was a nine-time Pro Bowler and was inducted into the Pro Football Hall of Fame in 1971.
Jim Brown —
Cleveland fullback Jim Brown, seen here reading a story about himself in the New York Daily News in 1965, retired from the NFL in 1966 at age 30. Brown played for the Cleveland Browns for nine seasons, winning the NFL championship in 1964, the last year the city of Cleveland won a major championship. Brown was a nine-time Pro Bowler and was inducted into the Pro Football Hall of Fame in 1971.
AP
Sandy Koufax, right, one of the best pitchers in MLB history, said in a press conference in Beverly Hills on November 18, 1966, he had asked the Los Angeles Dodgers to retire him because of painful arthritis in the elbow of his pitching arm. He was 30 at the time and had just won his third Cy Young Award after leading the Dodgers to the National League pennant.
Sandy Koufax —
Sandy Koufax, right, one of the best pitchers in MLB history, said in a press conference in Beverly Hills on November 18, 1966, he had asked the Los Angeles Dodgers to retire him because of painful arthritis in the elbow of his pitching arm. He was 30 at the time and had just won his third Cy Young Award after leading the Dodgers to the National League pennant.
AP
World heavyweight champion Rocky Marciano, seen here in 1955, announced on April 27, 1956, that he was retiring from boxing at age 31. Marciano, who had a perfect 49-0 record with 43 knockouts, said he wanted to spend more time with his family. He died in a plane crash in 1969 at age 45.
Rocky Marciano —
World heavyweight champion Rocky Marciano, seen here in 1955, announced on April 27, 1956, that he was retiring from boxing at age 31. Marciano, who had a perfect 49-0 record with 43 knockouts, said he wanted to spend more time with his family. He died in a plane crash in 1969 at age 45.
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