Fifth place in Abu Dhabi was a bitter disappointment for Valtteri, as it meant he finished the year in the same position in the Drivers' Championship - just a couple of points behind Max Verstappen, who jumped him by finishing on the podium.
"I think the race summed up the season quite well," Valtteri said, "it started off quite well and then went downhill."
Over the radio on the cool down, lap there was no mistaking the mutual respect between driver and race engineer Tony Ross, who moves on from the F1 team in 2019.
Chief race engineer Andrew Shovlin said: "I'd like to thank Tony for all his hard work over the last eight years. He will play a big part in our Formula E programme next year. He has contributed so much to the past five Constructors' Championships, and to Nico Rosberg's driver's championship, so we will all be sad to see him go, but happy we've had the chance to enjoy so much success together."
After winning three races in 2017, Valtteri considers 2018, in which he finished winless, the most disappointing season of his F1 career. But, he added: "I know that I performed better than last year. In the end, that's the only thing that matters after a season like this, one to learn from, one to kind of also forget but one that definitely will make me a tougher driver and person in the future."
He can take some solace from the fact that his one-lap pace over the season was so close to Lewis - a man who finished the year with 83 F1 poles to his name!
Stripping out qualifying sessions where issues for one or other rendered a comparison meaningless, although Lewis finished the season 13-5 ahead, the average margin between them was just 0.16s. Across the grid, only four team mate comparisons were closer: Sirotkin / Stroll at Williams (0.038s); Ocon / Pérez at Force India (0.10s); Hülkenberg / Sainz at Renault (0.13s); and Grosjean / Magnussen at Haas (0.14s).