MotoGP legend Valentino Rossi says the relationship between Sebastian Vettel and Ferrari in Formula 1 breaking down is "a great shame", as the German heads for Aston Martin in 2021.
Four-time F1 world champion Vettel joined Ferrari in 2015 following a six-year stint at Red Bull - with whom he won all of his titles - and scored his first win with the Scuderia just two races into their partnership.
Vettel mounted title bids in 2017 and 2018, but numerous driver and team errors cost both dearly, while the former went from winning five races in both campaigns to just one last year.
With it announced earlier this year that he would not remain with Ferrari in 2021, hopes of Vettel emulating Michael Schumacher's championship success with the Italian manufacturer have evaporated.
Commenting on his move to Aston Martin next year - which will be rebranded from Racing Point - Yamaha MotoGP rider Rossi believes "top driver" Vettel will be able to "demonstrate" his speed in 2021.
"For Vettel, it's a great shame because [it] finished in a bad way [the relationship between] Vettel and Ferrari," Rossi said ahead of the San Marino Grand Prix.
"Also, because they were very close to winning the championship one or two times, but they didn't.
"Now it's bad to see this situation because the car is quite slow and I think that Vettel is a top driver.
"So, I think he will demonstrate his speed next year with Aston Martin."
Vettel will take the place of Sergio Perez at Aston Martin next year after Racing Point informed the Mexican driver on Wednesday it would be parting company with him at the end of the season, despite having previously agreed a long-term contract.
Perez revealed on Thursday ahead of F1's Tuscan Grand Prix at Mugello that "nobody told me anything" about his imminent departure.
Vettel admitted he came "close" to retiring before being convinced of Aston Martin's potential.
F1's maiden outing at Mugello this weekend prompted Rossi to admit he is "very jealous" of the series, after the Italian GP had to be scrubbed from the 2020 MotoGP calendar due to COVID-19.
Having driven a Ferrari F1 car at Mugello back in 2008, Rossi believes the drivers "will enjoy" the "incredible" circuit.