Dr Helmut Marko has claimed that moving back to Toro Rosso will reduce pressure that Daniil Kvyat was struggling to cope with so far in 2016.
Opinions are divided over Red Bull's shock decision this week to promote teen sensation Max Verstappen to the senior team, resulting in the demotion of Kvyat.
The timing of the news was interesting, given 22-year-old Kvyat's controversial multiple crashes with Sebastian Vettel recently at Sochi and argument with the Ferrari driver after an incident in China.
One wild theory was that Ferrari might have pushed Red Bull to punish Kvyat.
"We have not been in contact with Red Bull," a spokesman for the Maranello marque insisted, according to Russia's Sportbox.
Marko did at least admit that the decision was taken after Kvyat's disastrous home grand prix last weekend.
"The decision was taken after Russia," he told Germany's Sport Bild.
"It was increasingly obvious that Daniil was not coping with the pressure with Daniel Ricciardo. We wanted to remove him from the line of fire and help his career, not harm it.
"I don't think it's a demotion. This year Toro Rosso is at a very high level and at the end of the year we can reshuffle the cards again.
"This also applies to Carlos Sainz, who has a chance of improving."
Marko also said that the move will be tough for Dutchman Verstappen.
"Max must now contend with Ricciardo, who is now at an incredibly high level," said the Austrian.
The season continues with the Spanish Grand Prix on May 15.
