In spite of their total lack of F1 experience this year, Toro Rosso's junior bulls produced some outstanding performances, with both Sainz and Max Verstappen often snapping at the heels of, and on some occasion even leading, their Red Bull counterparts.
Compared to the prodigious Verstappen, Sainz's season was somewhat dogged by bad luck and reliability issues.
Speaking at a Spanish media event at Jarama on Wednesday, Sainz delivered a pretty bold claim, but one which is not so unreasonable:
"In theory, we should be ahead of Red Bull next season," he said.
"The Ferrari engine has perhaps 50 or 60 more horsepower. For us that means between six and eight tenths of a second, while Red Bull was about half a second faster than us this season with the same engine.
"So in theory, we should be ahead. But I think Red Bull will have learned what their weaknesses are and they will also certainly have a better car in 2016."
Sainz conceded however that Red Bull's bigger budget and past success meant that the Milton Keynes outfit would always be a force to be reckoned with.
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