Nico Rosberg believes Ferrari need to work on their "team cohesion" suggesting the inability to properly back Sebastian Vettel hurt their championship bid.
Whereas Mercedes went all in on Lewis Hamilton for much of 2018, the Scuderia opted not to use Kimi Raikkonen as a support driver to Vettel with some speculation the Finn was also unwilling to help.
Either way, Rosberg pointed to that lack of support as a key differentiator between the title contenders which ultimately hurt their lead driver.
"They made so many strategy mistakes, also in team cohesion," said the 2016 world champion to Germany's Bild am Sonntag.
"It was weird because Ferrari always led the way with team orders, but as a driver, if you feel that you do not have full support, it can affect you in your mind and your focus.
"If you do not agree with your team - and in Sebastian's case rightly so - it is difficult."
Loking forward to next season, however, Rosberg is expecting another challenge from Maranello and backs Vettel to remain a strong contender.
"Basically, Ferrari just needs to continue in 2019," Nico claimed. "They managed to build a brilliant car. On that basis, I trust them that they will come back very strongly from the winter break.
"I don't see 2019 as Sebastian's last chance. It's just another chance," he added.
"He had a tough year and took a lot of criticism, but it was exactly the same situation for me in 2015. Lewis drove perfectly and I made mistakes.
"What's important is that you build up the confidence again, and Sebastian can do that. He's still one of the best drivers out there."
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