The Spaniard’s second stop only came on the penultimate lap as Ferrari held out for a Safety Car which didn’t arrive, resulting in Sainz retiring with a power unit problem.
Vasseur denied that the strategy dented Sainz’s chances of salvaging points in the season finale, insisting that he struggled for speed at the Yas Marina Circuit.
“When you have to pit on Lap 20, you have no other option than to put on a second set of Hards because if you put on Medium, you will have to pit on Lap 30,” he explained.
“And the plan was – I don’t know if it was a plan – but the option was to go Hard-Hard and to expect that we would have a Safety Car or red flag.
“The issue is that it was not a matter of strategy, it was a matter of pace. We did not have the pace and in this case, or the strategy.”
Asked to reveal what Sainz’s planned strategy looked like pre-race, Vasseur said: “Lap 35 or something like this, to the reverse of the others.
“The others did 15-20 laps with the Medium and then 40 laps with the Hard. And the target was to do 40 laps with the Hard with part of the race in clean air and try to compensate part of the deficit.”
Vasseur also downplayed that equipping Sainz with the grippier Medium compound from the outset instead of the Hard tyre would have improved the outlook of his race.
“You can always try to redo the race and to say that, but I don’t think so,” he added.
“I think the issue was the pace and was not the Hard or the Medium. He was on track with the same tyres as Charles [Leclerc]. We had an issue and need to understand the issue. It was not the strategy at all.”
Sainz’s failure to add to Ferrari’s tally in Abu Dhabi saw the Italian marque miss out by three points against Mercedes in the battle for second in the Constructors’ standings.
Despite team-mate Leclerc claiming second, George Russell’s podium coupled with Lewis Hamilton’s ninth-place finish was enough to preserve Mercedes’ slim advantage.
However, Vasseur refuted the notion that Ferrari’s fate was sealed at the final race and pointed to several occasions over the season where the team lacked competitiveness.
“For sure Carlos was out of the pace today, that it’s clear and we have to understand why. But honestly it’s not today that we missed something,” the Frenchman argued.
“If you have a look on the championship, I think we had a tough event. We had Miami, we had Zandvoort in terms of pace and we had some events when we had a reliability issue, and this was much more painful than today.
“Today we had a strong pace as a team that we are able to fight for the pole position yesterday. We fight with the Red Bull almost all the race. I’m not sure that it’s today that we missed something.”