Fernando Alonso believes the aerodynamic developments conducted by McLaren in the second part of this season have left the team better positioned for 2019.
Following its switch from Honda to Renault power for this year, the Woking-based outfit was confident of moving up the grid.
However, a fundamental aero issue impacting its MCL 33 chassis left the team's performance well short of expectations.
Over the summer, McLaren attempted to solve its car's excessive drag and inconsistent downforce problems, and while results barely improved, Alonso believes the team's positive development work and improved knowledge will help it field a much better car next season.
"Since July we have been testing experimental parts for next year," said Alonso.
"There is a lot of optimism in the team with the direction the car took in the last couple of months.
"We understood our problems, we know last year our car was very competitive on the chassis side – we know that, we have the GPS comparison, we know the speed in the corners.
"The car last year, 12 months ago, was very competitive in some areas and we lost that level of competitiveness this year unfortunately.
"We understood why, so I think next year the team will be in a much better position and I am happy for them."
While he won't be racing in F1 in 2019, Alonso may very well have a chance to experience first hand McLaren's improvements in 2019, with CEO Zak Brown suggesting the team could call on the Spaniard's feedback in testing next season.
"I have spoken to Fernando about it. He is very open to it," Brown said.
"There's a lot he can contribute experience-wise. Carlos [Sainz] and Lando [Norris] are open to any ideas that will bring us experience.
"Fernando knows the team very well, Lando doesn't have that experience, and Carlos doesn't have that experience with us. It's something I'll be talking to him about.
"I'll go to Daytona for Fernando's Daytona testing and we're going to chat to him further then."