Esteban Ocon believes his pace deficit to Alpine teammate Fernando Alonso in last weekend's Russian Grand Prix was likely due to set-up differences between the two drivers' cars.
Alonso qualified sixth in Sochi, three spots ahead of Ocon and raced competitively well among the top-ten all afternoon, crossing the checkered flag P6 at the end of the day.
The good performance contrasted with Ocon's day which the Frenchman spent for the most part outside of the first half of the field, concluding his race a lowly 14th in the running order.
This year's Hungarian Grand Prix winner admitted that he had probably endured in Russia "one of the most difficult Sundays of the year".
"I think the positive was the start and the first couple of laps, that was pretty good," said Ocon.
"I gained a bit of ground at the start and we managed to stick in a good position for the first couple of laps but after that it was pretty tricky pace-wise.
"We were lacking quite a lot of lap time lap-by-lap and losing ground to the car in front, not being able to attack or defend against any of them to be fair.
"Quite a lot of things for us to review, quite a lot of work before getting to Turkey, but we will find what was wrong at this race and come back stronger at the next one."
Asked why his performance on race significantly lagged that of Alonso, Ocon pointed to a divergence in set-ups between Alpine's two A521 cars.
"The cars were very similar in terms of set-up at the last three or four races – pretty much identical," he explained.
"But there’s been quite a lot of deviation at this race and we don’t have the same comments anymore from this race.
"We have a couple of ideas what it could be, and we’re looking at fixing it for the next race.
"I feel good at the wheel, like I’ve been feeling good at Monza or Zandvoort the same. So there is no particular reason [for the underperformance] on my side."