Sebastian Vettel and Lance Stroll were only one point short of outscoring Alfa Romeo and securing P6 in the Constructors' Championship.
Instead, their combined points finish meant they completed the season level on 55 points, but because of a fifth place at the Emilia Romagna Grand Prix from Valtteri Bottas, the Swiss team finishes the season ahead.
Vettel was audibly not happy with the strategy during the race, and complained about the team's decision to complete a one-stop strategy.
After the race he doubled down, believing the team threw away their shot at finishing higher.
"It was absolutely the wrong strategy, so it was a shame we went backwards," Vettel told media, including RacingNews365.com.
"I really tried, but I gave everything I could.
"It would have been great to give the team sixth place, but we threw it away with the strategy we chose."
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Vettel enjoys his last race
Vettel's final race featured several overtakes as he fought back through the field, and commented on the respect he was shown, notably from Fernando Alonso who said that he would not attack him during the first lap.
He said: "I saw it especially with Fernando at the beginning of the race."
"After that it was hard, very hard for the Alfa Romeos. Of course, they wanted to defend their place in the Constructors'.
"It was a shame that I was stuck behind Esteban Ocon earlier in the race, because I had better tyre degradation. We were stuck for too long, so we lost too much time."