Rossi to start at back for MotoGP title decider after Marquez clash

Rossi appeared to deliberately run into Marquez as they fought for third early in Sunday's Malaysian Grand Prix, causing the Honda rider to crash out.

The pair had been embroiled in a ferocious fight, passing and repassing each other multiple times, with Rossi having already already gesticulated at his rival in frustration.

He then slowed and ran wide into Marquez at Turn 14, turning to look at the Spaniard as he did so.

The incident was immediately investigated by race direction, which ruled that Rossi's riding merited three penalty points.

Added to the one penalty point he had received for delaying Yamaha team-mate and title rival Jorge Lorenzo in San Marino GP qualifying last month, that means Rossi will start the Valencia GP from the back under MotoGP's penalty system.

He leads Lorenzo by seven points in the championship, after finishing third behind the Spaniard at Sepang.

The Rossi/Marquez clash in the race marked a further escalation of the bitterness between the pair.

Their once cordial relationship had declined following disagreements over incidents at Termas de Rio Hondo and Assen earlier in the season.

Rossi then accused Marquez of "thinking like a child" in the build-up to the Sepang race, suggesting he had tried to deliberately hamper him at Phillip Island last weekend.

The Italian chose not to attend the post-race press conference following his podium finish.