Helmut Marko has claimed that Ferrari was fastest on both the Hard and Medium tyre during the Canadian Grand Prix, which posed a potential threat to Max Verstappen.
The Red Bull advisor said Verstappen had problems getting temperatures into the Hard compound during his middle stint, which the team largely put down to the long straights which cool the tyres around the Circuit de Gilles Villeneuve.
This left them vulnerable midway through the Grand Prix, as it enabled both Fernando Alonso and Lewis Hamilton to close the gap while they were racing for second.
It was telling that Verstappen's win margin was a lot lower than previous races, with him crossing the line just 9.5s ahead of Alonso.
"It wasn't easy, we had problems with the Hard tyres to get them up to temperature. The race was harder than we thought," Marko told ServusTV.
Marko was relived that both Ferrari's started outside of the top five, after he previously warned about their pace shown during Friday practice.
He added: "But luckily Ferrari started further back, as they were fastest on both sets of tyres."
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Marko: Verstappen was distracted by the TV!
While leading the race, Verstappen had two significant moments which could've ended in disaster.
Midway through the race he hit a rogue bird, which got lodged between the front right brake ducts and almost caused a failure or unscheduled pit stop.
The Dutchman had another hairy moment when he bounced off one of the raised kerbs at the apex of Turn 9, narrowly avoiding the barriers after George Russell also did the same earlier in the race and caused significant damage to his car.
Verstappen remarked that he "almost knocked myself out" over the team radio, while Marko believes it happened because his attention was elsewhere.
"Maybe he was looking at the TV screens, he often does that!" exclaimed Marko.
"But it's incredible what kind of overview Max has and what kind of overcapacity he has."