Ferrari team principal Fred Vasseur believes that Formula 1's backmarkers disobeying blue flags ultimately cost Charles Leclerc second in the 2024 Mexico Grand Prix.
Leclerc had a gap of over three seconds to Lando Norris going into the final 15 laps of the 71-lap affair at the Autodromo Hermanos Rodriguez, but had to watch his advantage dissipate when the two started to lap traffic - encountering Lance Stroll, Liam Lawson and Franco Colapinto.
The Monegasque then cleared the now-lapped with about half of that initial advantage, which Norris was able to close down and begin applying pressure. Leclerc then went wide at Peraltada at the end of lap 62 and saved his Ferrari from succumbing to a snap of oversteer - which let Norris through.
Vasseur disagreed with an assessment that Norris was faster in the closing stages, stating that Leclerc lost time and tyre temperature wrangling with the traffic - particularly Stroll, behind whom Leclerc lost most of his advantage.
"It's your analysis [Norris was faster] but I'm not really aligned," said Vasseur. "I think that Charles had good pace, but we lost three seconds with the guys who were blue-flagged.
"And we also lost a lot of temperature in the tyres at this stage and he made a mistake, but I think from the beginning, the race was under control.
"Charles was not happy yesterday with P3 or P4, but still today he did a good race. I'm a bit upset with the story with the blue flag, it cost us P2. But at the end of the day, it is like it is, but we have to be focused now on the next one and forget this one.
"When you do five corners when the guy has a solid blue, it's not unfortunate. It's a mistake of the guy."
Elaborating further when speaking to Sky Sports F1, Vasseur stated that "[Leclerc] lost three or four seconds into the traffic with some idiots. Norris came back, Charles pushed a bit too much. Perhaps he lost also a little bit temperature in the tyres when he was with these guys.
"Honestly, they have to respect the blue flag and I don't understand why the FIA didn't give them a penalty. We had four seconds on Norris. And after the three guys, we were 1.2 or 1.3 ahead."
Leclerc suggested that he had "no chance" of beating Norris when the McLaren driver began to close, stating that his clash with Max Verstappen had helped Ferrari build something of a buffer.
"Lando was flying, and I think as a team, we've been pretty lucky that whatever happened with Max and Lando at the beginning of the race, that slowed him down massively," said Leclerc.
"His second stint was very, very impressive. On my side, there was no way that I could stay in front. I knew that it would be very difficult.
"I knew that I had to have an incredible exit out of the last corner, so I tried to put everything to have a really good exit, went over the limit, lost the car and lost the position, but I felt it was a question of laps or corners before I lost that position."
