Hiroshi Aoyama has spoken out in tribute of his Gresini Honda team-mate Marco Simoncelli following his death during the Malaysian Grand Prix.

Aoyama and Simoncelli, former rivals in the 250GP class, landed as MotoGP team-mates in 2011 after the Japanese rider switched to the Gresini squad.

Writing on his personal blog, a clearly devastated Aoyama says he is struggling to find the words to describe the situation.

"My team mate Marco crashed during the race. He was fighting hard for his life but unfortunately he passed away. I cannot think of any words to describe this tragic loss.

"He has been my rival since the 250's and since we both started in Moto GP class, I could feel the tension in between us and we were always aware of each other as rookies. And now, we have been competing in the same championship as a team mate. He is such an openhearted person, no matter where he is. I know everyone had a high expectation of him since he has been performing so well.

"He is loved by so many people and I know why. Last week he came second and was on the podium. And this week again he was so powerful on his bike..... but why.....? How.....? That is all I can think right now.

"I would like to give my condolences to Marco's family, fans, teams and staff. Rest in peace Marco."

With Gresini Honda considering missing the final round of the season at Valencia, Aoyama, who is already confirmed as joining Honda in the World Superbike Championship next year, may have made his last appearance at MotoGP level.