Valentino Rossi will lose trusted mechanics Alex Briggs and Brent Stephens when he moves to the Petronas Yamaha team next season.

Briggs inherited The Doctor when Jerry Burgess was employed as his crew chief in 2000 following the retirement of Mick Doohan in 1999 while Stephens was placed with Rossi in 2004.

Both mechanics have gone with Rossi wherever he has roamed - which is unusual - including his Ducati years but this will be the final season for them.

"I have known since Jerez that there is no place for me in the Monster Factory team next year," Briggs wrote on Twitter this morning.

"So I am now a free agent and would consider offers but most likely will stay in Australia next year."

It is believed that only crew chief David Munoz, data engineer Matteo Flamigni and rider analyst Idalio Gavira have survived the chop.

"I am very sorry for Alex and Brent. they wanted to follow me and I tried but it wasn't possible. hey both told me they would retire with me. It will be sad not to have them in the garage. They are members of the family," said Rossi, speaking at the track.