Dr Helmut Marko does not believe Pierre Gasly would have been able to recover his performance levels if he were left in Red Bull's line-up in 2019.
Gasly was demoted back to Toro Rosso and replaced by Alexander Albon over the summer break, but the Frenchman has regained his confidence in the sister team and secured his maiden F1 podium at the Brazilian Grand Prix.
Marko was a key factor in the decision to demote Gasly, who will remain with Toro Rosso in 2020.
"He's recovered, and now we see the real Pierre," Marko told Motorsport.com.
"We always believed in him. It was positive for him, otherwise at Red Bull Racing I think he never would have recovered."
Interlagos was a fine weekend for Red Bull, with Max Verstappen winning from pole, although Albon was denied his own maiden podium in a collision with Lewis Hamilton on the penultimate lap.
With Daniil Kvyat having also taken a podium with Toro Rosso this year in Germany, Marko says the Red Bull programme – which was becoming maligned this time last ear – is thriving once again.
"Max was perfect, his overtaking manoeuvres were unbelievable," Marko said.
"And Albon also did very well before he was pushed off. So it shows our programme is working. We're very excited about next year."