Spain's three-time MotoGP champion Jorge Lorenzo will retire from the sport after Sunday's final race of the season in Valencia.
Lorenzo was champion in 2010, 2012 and 2015 with Yamaha and also won two world titles at 250cc in 2006 and 2007.
The 32-year-old made his MotoGP debut in 2008 and won 47 races, fifth on the all-time list, finishing on the podium 114 times in 202 starts.
He joined Repsol Honda for the 2019 season and is 19th in the standings.
"The day has arrived, this will be my last race in MotoGP," an emotional Lorenzo said at a news conference on Thursday. "At the end of the race I will retire as a professional racer."
Lorenzo, who had another year left on his contract with Honda, has suffered with injuries and struggled for form this season.
He missed four grands prix after crashing and fracturing a vertebrae during practice at the Assen Grand Prix in June.
"I love this sport but above all I love winning," said Lorenzo.
"I have let myself down and I have let down Honda but I think this is the best decision for me and the team. We are both winners and we always have to fight to win."
His departure leave a vacancy at Honda alongside fellow Spaniard and six-time MotoGP champion Marc Marquez.