Lorenzo ended the three-day test in 10th place overall, three tenths slower than works teammate Andrea Dovizioso and narrowly outpaced by Pramac's Ducati GP18 rider Danilo Petrucci as well.

The Spaniard said the three pre-season tests were not enough time to fully develop the bike and get him accustomed to the new-spec Ducati.

"We just had three tests so it is very little to make a great evolution during the pre-season so that is why still we have a big margin for improvement in the future," said Lorenzo.

"I still don't feel this bike natural for me. I still don't feel that is really my bike.

"It is a matter of understanding what is the best setting, the best combination for my riding and when it happens I will be fighting for the top, fighting for victories and good results."

The three-time world champion's comments are in contrast to his initial impressions of the GP18 at the start of pre-season testing in Sepang, when he claimed the new Ducati was "more Lorenzo's bike" and "much more close to my natural style".

Lorenzo remains convinced the GP18 is a "clear step forward", but insists Ducati's rivals have also improved, which makes it more difficult to be more competitive.

"We make a clear step forward compared to last year but also the rest [improved]," he added. "Honda improved the engine a lot, Suzuki also goes very well and so does the Yamaha, as shown by [Maverick] Vinales.

"The bike is competitive but every rider needs a different kind of configuration, setting. We need to understand what is good for you, the ergonomy of the bike, everything.

"In this category, the evolution never stops for all the teams and you need to be always fighting to improve tenth by tenth, every month."

Additional reporting by Oriol Puigdemont