The first sector of the circuit, which includes eight turns, is largely comprised of a run of high-speed kinks.
Horner says in that particular area of the track Verstappen had an edge that ultimately enabled him to outpace Perez and claim victory.
The Dutchman started the race from ninth place after a red flag ended Q3 before he could complete his final flying lap, while Perez was on pole.
They took opposite strategies for the race, with Verstappen’s hard/medium choice ultimately beating Perez’s more obvious option of medium/hard.
Verstappen showed impressive pace throughout, notably when he was on older hard tyres than Perez in the middle part of the race.
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“It's just purely sector one, I think [Turns] 3, 4, 5 and 6,” said Horner when asked where Verstappen had the advantage.
“Max was outstanding in that sector. And I think the rest of the lap was much of a muchness. But sector one was where Max was really doing a lot of damage.”
Asked to expand, Horner added: “I think it's the way that the sequence of corners flows. It's hard to pinpoint any particular area of consistency.
“I think that Max was on fire through that sector all weekend. But it will vary from circuit to circuit.”
Horner added that when their opposite strategies converged close to the end of the race, the two drivers stuck to their promise to treat each other with respect during a brief tussle, before Verstappen completed the inevitable pass.
“We discussed it [on Sunday] morning,” said Horner. “I said to them you're free to race, but just keep it clean. And respect the team and respect each other.
“I felt they did that. They raced firmly but fairly, and they gave each other enough space and respect.”
Horner stressed that despite losing out after starting from pole Perez could still be pleased with his overall performance.
“Max was truly outstanding. But there's still a long, long way to go,” he said.
“I think there's only 14 points between the two drivers, and 18 races to go and five sprint races.
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“So still an awful lot that can happen. I'm sure [Perez] was disappointed not to convert it into a victory. But he's still taking away very valuable points.”
He added: “I think he'll want to understand where that time difference was in the middle part of the race.”
