Valentino Rossi insists Yamaha must improve over the course of the weekend if he is to have any chance of securing victory at the Italian Grand Prix in Mugello. 

Rossi was sixth-fastest in free practice two on Friday after failing to set a time, along with several others, in a rain-affected FP1. 

However, the top-10 were separated by just 0.774seconds in the second session, and Rossi knows every little bit will count if he is to compete for a podium on Sunday.

"It's always difficult here. Mugello is one of the best tracks but it's very demanding and scary, you have to be very courageous because it's very fast," the Italian said.

"It has a great layout but it's difficult to find the right setting. Unfortunately, we lost time this morning due to the weather and we are not OK with the balance of the bike, but for the first practice it was not so bad. 

"The problem is that we are all very close so we have to improve, because especially in the last sector I'm not fast enough."

Rossi stressed a top-five qualifying position as integral for securing maximum points in Mugello, especially with his struggles off the line so far this year.

"It's very, very important if I want some change to fight at the top I need to start top five," he said. "First row in more important but also top five is OK.

"This morning we didn't want to waste time and we had the chance to practice our starts, because this year we have some more problems with the clutch at the starts and we tried some different stuff, so at the end it was an important test."