Bagnaia and his Ducati factory teammate Jack Miller were the only two riders to use the hard front in Sunday’s cold Misano race, with the latter crashing on lap four.
Bagnaia, who led the race for the first 22 of 27 laps, made his choice and withstood pressure from eventual race winner Marc Marquez and was on course to keep his title hopes alive while Fabio Quartararo was just fourth.
But Bagnaia crashed on Lap 23 as he lost the front of his Ducati through Turn 15 on the left, just as Miller did earlier in the race, handing the title to Quartararo.
Rossi has previously spoken out about trying to influence Bagnaia’s tire choice at races and believes the Ducati rider should have run the middle front instead – although Bagnaia later admitted he wasn’t comfortable on that compound.
“Pecco has had a fantastic season,” said Rossi.
“I’m a bit mad at him today because I think if he puts on the middle front he could win because he was the fastest.
“But that’s my opinion. He had a great chance to keep the championship open.
“It was difficult anyway, but bringing it to Portugal was important. But it is, but I think Pecco, Franco [Morbidelli]also Luke [Marini] will be very strong next year.”
Valentino Rossi, Petronas Yamaha SR, Luca Marini, Esponsorama Racing
Photo by: MotoGP
Rossi made his final MotoGP appearance on home soil on Sunday, starting from last to finish tenth for only his third top 10 finish of 2021.
The nine-time Grand Prix World Champion felt it was the “best way to say ciao to his home fans”.
“I’m happy about today because I set a decent pace,” added Rossi.
“I’m very happy, that’s the best way to say ciao. I didn’t want to have a bad race and fall behind, so I tried to stay focused and it’s always difficult to start from the back.
“But I felt good with the bike and the tires, I know my potential is better when it’s completely dry.
“I was able to do some overtaking manoeuvres, fought some battles until the last lap and ended up in the top 10.
“So it’s the best way to say ciao to the crowd because there was a fantastic atmosphere around the track.
“There were a lot of fans, it was a sunny day, so I’m happy. It was good, it was very, very emotional.”