In a Qatar Grand Prix dominated by newly crowned three-time world champion Verstappen, team-mate Perez climbed from a pitlane start to classify 10th – but only after copping three five-second penalties for exceeding track limits on six occasions.
Amid Perez’s ongoing struggles, Red Bull team boss Horner said his driver now needs to be sat down and “go back to basics” to rediscover his confidence ahead of the United States, Mexico and Brazilian GP triple-header.
But for now he believes Red Bull has lost a driver pairing – comparable to the evenly matched McLaren (Lando Norris, Oscar Piastri), Ferrari (Charles Leclerc, Carlos Sainz) and Mercedes (Lewis Hamilton, George Russell) line-ups – which it could rely upon earlier in the season.
“I think with a car like we have, he's probably putting that pressure on himself,” said Horner.
“The most important thing for us is winning both [drivers’ and teams’] championships. We've done that.
“And then, what's the next best thing after that would be to have both your drivers first and second.
“You can see Mercedes have a pair, McLaren have a pair, Ferrari have a pair that are quite tight between the respective drivers.
“I think we've had that at the earlier point in the year. But as the season has gone on it's become more variant.
“We just need to get Checo back to the best form that he's capable of.”
Horner believes that it is Perez’s mental, rather than physical, condition holding him back presently, although the Mexican is working with a psychological coach.
Asked if he was concerned about carrying a mismatched driver pairing into next year, with Perez under contract for 2024, Horner added: “The frustration is that we know what Checo has been capable of doing.
“Of course, last year and this year, he's contributed significantly to the constructors’ championship. We desperately want him to find that form and as a team; we need him to.
“We can't afford to have a big split because if, as you would expect, the grid continues to concertina next year, we need both drivers delivering at the top of the game.”
Horner insisted Red Bull is “going to give all the support that we possibly can” to help Perez amid speculation the team could change its driver line-up early next year.
