(REUTERS) - Italian great Valentino Rossi blasted a Spanish "stitch-up" on Sunday, after Yamaha team mate Jorge Lorenzo won the final round of the season in Valencia to take his third MotoGP world championship.

Rossi had started in last place, after being sent to the back of the grid for a penalty imposed at the previous race in Malaysia, and with his sole title rival Lorenzo on pole position.

The championship leader had fought back to fourth by half distance but his hopes of taking a 10th career title, and eighth in the top category, rested on Honda's two Spaniards getting past Lorenzo.

In the end outgoing champion Marc Marquez and Dani Pedrosa finished second and third and Rossi angrily accused them of helping their compatriot by not trying to win.

"I did what I could but it was a strange situation having Marquez as the bodyguard of Lorenzo. It is embarrassing for the sport," he told reporters after former king Juan Carlos handed out the winner's trophy on an all-Spanish podium.

"Hopefully the sport's authorities will be able to sort it out. It is an ugly end to what has been an attractive championship. It has not been a true championship and this should not happen in sport," he added.

Rossi said Lorenzo was a deserving champion but he could not understand why Honda, his former team, should want to see a Yamaha rider win.

He accused Marquez of being a "biscottone" - an expression used in football when two teams play out a mutually beneficial draw to the detriment of another - but said he expected no less.

Marquez said it was "a lack of respect" to suggest he had not tried to win even if he recognised there would always be doubters. "I always give everything and I know there will be people that will say that I have been second because I wanted Lorenzo to win," he said.

Lorenzo, who ended the season with seven wins to Rossi's four and five points clear, suggested it was to be expected that his compatriots would rather see him win.

"The fact that they knew what I was going for and that they are Spanish has helped me and in another race they may have tried everything to overtake," said the new champion.

"Dani did well because he could have tried a crazy overtake. We are Spanish and the title remains in Spain. If it had been in Italy and with two Italians behind Rossi then it would have been the same."

The race had been overshadowed by controversy and bad blood since Malaysia, where Rossi allegedly kicked Marquez off his bike. Rossi denied that, accusing the Spaniard of trying to sabotage his title hopes.

A bid to persuade the Court of Arbitration for Sport (CAS) to overturn the back-of-grid penalty failed, although the appeal against the sanction remains in process.

The prime ministers and media of both countries got involved in the row, while Marquez and his family filed a legal complaint after allegedly being assaulted by Italian journalists.

The race itself was far more tame, with Lorenzo leading from start to finish while Rossi climbed as far as he could and then waited to see what happened with the top three too far ahead to catch.

The Italian finished 19.7 seconds behind the winner, who beat Marquez by a mere 0.2.

Among the cheers, whistles and boos could also be heard clearly as the top three made their way to the podium.