Johann Zarco feels a difficult start to Tito Rabat's MotoGP career, combined with the limited testing available made it harder for the Spaniard to fully adapt to the premier-class.

After being Moto2 rivals and world champions during 2012-2015, Zarco eventually became Rabat's MotoGP team-mate at Avintia Ducati this season.

While the Frenchman went on to secure the team's first pole position and podium, clearing the way for a Pramac Ducati move and upgraded machinery for 2021, Rabat scored a best finish of eleventh and is leaving MotoGP to make way for Luca Marini.

It's now been officially confirmed that the Spaniard will make a fresh start in the World Superbike championship next season, riding for Barni Ducati.

With a best result of seventh to show for his five MotoGP seasons - two at Marc VDS Honda then three at Avintia Ducati, but missing half of 2018 due to serious leg injuries - it's easy to forget Rabat's formidable Moto2 form.

His title-winning 2014 campaign produced 14 podiums (including seven wins) from 18 rounds, to comfortably beat the likes of former/future MotoGP riders Mika Kallio, Maverick Vinales, Thomas Luthi and Zarco.

An attempt to become Moto2's first-ever double champion the following season saw Rabat lose out to Zarco and another future MotoGP star, Alex Rins.

However, Rabat – who broke his collarbone and then wrist during separate training accidents - still took three more victories (and ten podiums) before joining the premier-class with Marc VDS in 2016.

"For Tito, the overall memories are the Moto2 years where he was pretty strong, winning the title, and then fighting with him for his second title when I got my first," said Zarco, who went on to become Moto2's only double champion to date in 2015-2016.

"It's a pity that in MotoGP he didn't find the opportunity to really adapt well."

Both Rabat and Zarco waited a long time to become a world champion, Zarco finally succeeding in his seventh Grand Prix season and Rabat his ninth.

While Zarco has remained largely competitive, barring the KTM kerfuffle, Rabat suffered a difficult debut MotoGP season and has hovered between 19th and 22nd in the championship standings ever since.

Zarco believes the uncompetitive nature of the 2016 satellite Honda (team-mate Jack Miller had a best dry result of tenth) made it more 'complicated' for Rabat to understand how a MotoGP machine needed to be ridden and he may have lost his way.

"Maybe he started in MotoGP with not a very competitive bike, at the beginning it was the [satellite] Honda, so it doesn’t help you to understand if you are doing good or not," Zarco explained. "I think this was complicated for him."

Part of Rabat's Moto2 success was also attributed to a relentless training schedule on a similar 600cc bike around Almeria, but the unique nature of a MotoGP prototype meant nothing could prepare him for the premier-class.

"He's a totally passionate guy, fully motivated. He's the one riding motorbikes the most, but this MotoGP category for his style he could not adapt well because he needs to ride a lot to adapt," Zarco said.

"Unfortunately, with the MotoGP bike we can't ride that much and if you don't get it [how to adapt to MotoGP] quickly then you struggle and I think this has been his situation for many years."

The switch to WorldSBK means Rabat will once again have the opportunity to carve his own groove around practice tracks during training, this time on a Panigale road bike.