Rossi "worried" about lack of pace ahead of Qatar opener

While new teammate Maverick Vinales has pulled off a clean sweep in off-season testing, going quickest in Valencia, Sepang, Phillip Island and Qatar, Rossi himself has languished behind of the Spaniard for most of the running.

Rossi found encouragement in his laptime during the second day of the final Qatar test, but was back to square one on the final day, finishing 0.855s behind Vinales.

"We had a programme, but unfortunately I didn't have the same feeling and the same speed," Rossi said. "Looks like the condition of the track changed a bit, and we were not able to follow, to improve.

"I don't have the same feeling as yesterday, and I was a bit slower - a lot more effort, to be slower."

Rossi admitted he and his team were still not fully prepared for the March 26 season opener in Qatar.

"I think that we are still not ready, we don't understand 100 percent the way to make this bike work at the maximum.

"We are a bit worried - because at the end, except some good laps, the winter tests were very difficult. Now we have to speak together and try to be stronger of the first race."

Vinales understood bike quicker

Rossi, who turned 38 in February and whose contract with Yamaha runs through 2018, insisted he did not think this year was his last chance to challenge for an eighth premier-class title.

"It's not the last chance, because I will race for two seasons at least, and after we see. It's the same," Rossi said.

"All these stories are good to write at the beginning of the championship, but at the end, we have to wait [and see] what happens.

"Looks like the bike has good potential because Vinales is very fast, but I think that he and his team are able to understand in a shorter time the way to make this bike at the maximum.

"We are a bit in delay, so we are a bit worried. We hope we can be stronger for the first race."

Additional reporting by Oriol Puigdemont