Bernie Collins has revealed what she believes was "the biggest thing" to have cost Lando Norris in his title bid against Max Verstappen.
Norris' hopes of a maiden Drivers' Championship were all but ended on Sunday as Verstappen came from 17th on the grid to win the Sao Paulo Grand Prix, while the Brit dropped back from pole position to finish sixth.
The result saw Red Bull's Verstappen extend his lead over Norris to 62 points with just 86 points available over the remaining three rounds, meaning an extraordinary set of circumstances would be required to give the McLaren driver genuine hope of victory.
Despite appearing to have had a car capable of challenging for victory at just about every race since McLaren brought upgrades to the sixth round of the season in Miami, Norris has claimed only three wins in 16 grands prix since.
The latest missed opportunity came on Sunday at Interlagos, where a questionable call to pit in the wet enabled Verstappen to gain track position.
Speaking on the latest episode of the Sky Sports F1 Podcast, former Aston Martin head of strategy Collins said: "The biggest thing for me seems to be this indecision or lack of trust between driver and pit wall that has caused hesitation at some decisions at some points in the year.
"They'll be working on that and every year the relationship will improve, he'll be more confident going into next year.
"The starts seem to have got better, maybe not explicitly this week with Russell off the line, but McLaren will look at that again, it's very different in wet conditions.
"So that will come, he'll take a lot of time to reflect over the winter."
Listen to the latest episode in full to hear Bernie Collins and Karun Chandhok analyse Max Verstappen's stunning victory and a shock double podium for Alpine. Subscribe now on: Apple Podcasts | Spotify | Spreaker
Chandhok: Title battle wasn't lost in Brazil
While Norris has undoubtedly had the most consistent car on the grid since Miami, at that point he had already given up a significant advantage to Verstappen.
The Dutchman, who is set to claim a fourth successive drivers' title, won four of the first five races of the season to open up a 52-point advantage over Norris.
Sky Sports F1's Karun Chandhok believes Norris was never "realistically" going to close the deficit.
"I think realistically, they can be proud of the season he's put together," Chandhok said on the Sky Sports F1 Podcast.
"The championship battle wasn't lost on Sunday in Brazil. It was lost in the first five races.
"If you rewind the clock to the opening five races of the season, that's where Verstappen really got this big advantage. Very reminiscent of what we saw from Jenson Button back in 2009.
"On the whole, they can be pleased with the season they've had, they can be pleased with the points they've scored, but when you start 52 points behind coming into Miami, that's where the championship was lost, not on Sunday in Brazil."
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