MotoGP world champion Marc Marquez was appalled by Valentino Rossi's riding in their fight during the Malaysian Grand Prix, the Spaniard saying he had never seen a rider kicking a rival.
Honda rider Marquez crashed at Turn 14 during the race after Rossi forced him wide and then appeared to use his leg left to make contact with the Spaniard.
Rossi went on to finish in third place, and although the incident was investigated, the Italian was only handed a penalty for the season finale at Valencia, where he will start from the back of the grid.
A baffled Marquez admitted he had never seen anything like today's incident, and reckons Rossi was just nervous.
"Valentino overtook me, I followed him for half a lap, and I saw that I could go faster than him, so I tried overtake him back," Marquez said.
"We started a fight between us and I always passed without making any contact with him.
"At Turn 14 he passed me on the inside, I sat the bike up, he kept going straight ahead and I saw him looking at me. I didn't know what to do.
"Then he kicked out at me, knocking my brake lever, and I crashed.
"Both what Valentino said to Race Direction and what he did on the track has made me disappointed. I've never seen anything like it: a rider kicking another rider.
"It might be down to nerves, but I want to try to forget about all this and the important thing is that I'm fine physically. I hope, for the sake of the sport that this ends here."
An angry Rossi said after the race that Marquez had cost him the title.
The Yamaha rider is now seven points ahead of teammate Jorge Lorenzo, second today.
Two-time world champion Casey Stoner, a former rival of Rossi, took to Twitter to say the Italian's riding had been inexcusable.
"If anyone else had done what Valentino did we would have been black flagged immediately, no questions asked," Stoner wrote.
"There is a massive difference between reckless riding and intentionally taking someone out."