Stefan Bradl has confirmed he will leave the MotoGP World Championship at the end of this season.
The German stepped up to the premier-class as the reigning Moto2 title holder in 2012, scoring his only MotoGP podium and pole position with LCR Honda the following year.
Bradl switched to Forward Racing in 2015, then Aprilia from the middle of the season onwards.
But Aprilia have chosen an all-new line-up of Sam Lowes and Aleix Espargaro for 2017, with Bradl's MotoGP exit confirmed after negotiations broke down with Avintia Ducati.
“Next year I will not be in grand prix racing,” Bradl told Speedweek.com
“I greatly appreciate the efforts made by Avintia, who have constantly improved their offer... But some details at Avintia did not fit, so there has been no agreement.”
The German is now set to switch to the World Superbike championship, with Honda the hot favourite to land the seven-time grand prix winner (five in Moto2, two in 125cc).
Bradl, who compared his decision to leave MotoGP with the successful switch from 125cc to Moto2 at the end of 2009, may not be the only rider moving from MotoGP to WSBK next season with Aspar's Eugene Laverty examining offers in both championships.
Despite Bradl's departure, Germany will still have one rider in the MotoGP class next season with rookie Jonas Folger joining Tech 3.
Bradl - ruled out of his recent home race due to a concussion - is 15th in the standings, three places ahead of team-mate Alvaro Bautista, who is expected to join Aspar Ducati.