Although Perez missed out on a podium finish to Fernando Alonso in last weekend’s Brazilian Grand Prix by just 0.053 seconds, it was still his most competitive weekend since he finished second at the Italian Grand Prix back in September.
Perez felt he was on course to join race winner Max Verstappen on the front row until he was hampered by a yellow flag in Friday's qualifying session, caused by Oscar Piastri's final corner excursion ahead of him, forcing the Mexican to start ninth.
Following massive progress he made in a mammoth three-day simulator session at its Milton Keynes factory prior to the United States Grand Prix, Red Bull says that Perez's step forward is now genuine.
“I thought he drove brilliantly well,” said Horner about the Brazilian GP weekend.
“He had a little bit of a wobble at [Turn] 2, which allowed Fernando, who was pretty quick on the straights today, to have a go. He did his best to hang on to it though.
“But I think for Checo to outscore Lewis [Hamilton] by 12 points this weekend, it's been a very strong weekend for him.
“A third in the sprint, fourth from ninth on the grid with the yellow flag he got in qualifying, I think there's been very good points for him.”
Asked what exactly had changed to help Perez appear to be so much more comfortable with the RB19, Horner said: “I think he's focusing more on the basics. And I think that's coming together for him.”
Perez had felt that the pre-Austin simulator work had given him what he needed to deliver podium form for Red Bull – but opportunities had slipped through his fingers in both the USA and Mexico.
However, having come so close to producing two podiums in Brazil, Horner felt that it had been a significant weekend for Perez.
“I think it was important for his confidence,” said Horner. “This is the Checo that we know, and we know what he is capable of.
“It will give him just the boost he needs going to Vegas, another street track that he always performs well at. And then it’s Abu Dhabi one week after.”
