Dr Helmut Marko has revealed a "tense" mood inside the Red Bull garage ahead of the Belgian GP.
Both Max Verstappen and his long-time race engineer Gianpiero Lambiase were chided by the team’s famous F1 advisor after Hungary for their radio behaviour.
"The two of them sat down together and discussed it," Marko told Kleine Zeitung.
"The mood is a bit tense," he added, also admitting to the Austrian journalist that triple world champion Verstappen is personally "more tense" than usual as well.
"It’s a tough season for him and he’s only human," said Marko. "We’re still in the lead, but not as dominant anymore."
Indeed, Verstappen still seems to be in a frustrated mood at Spa on Thursday, telling those who object to his in-race radio messages to "turn the volume down".
As for his arguments with engineer ’GP’, the 26-year-old responded: "We are very open, very critical of each other, but that has worked very well for us, so I don’t expect that to change."
What Verstappen is unhappy about, however, is Marko’s reported "ban" on his late-night sim racing sessions.
"I don’t have a ban," the Dutchman hit back. "I don’t tell them what to do in their private time at the weekend. That also applies to me the other way around.
"We’ve talked about it," Verstappen added. "There are no new sim races coming up, so I said he doesn’t have to worry. I’ve been doing this since 2015 anyway, it’s important for my life.
"I’ve won three world championships. I know what I can and what I cannot do."
The really bad news for Verstappen is that he will be taking a grid drop for having unscheduled fresh engine components fitted at Spa, but he says "we’ve known what was coming for a long time so it’s not a nasty surprise".
"The weekend will show how far we can advance up the field. We haven’t had the fastest car in the last few races, so we can’t say we’ll win, but a lot can happen in a grand prix.
"McLaren has put the best car on the track in the last few weekends and if that continues, it will be close at the end of the championship," said Verstappen.
Meanwhile, both Sergio Perez and Daniel Ricciardo’s places at Red Bull Racing and the junior squad RB are in doubt beyond the looming summer break.
"We need consistency," Marko said.
"Christian Horner and I will sit down on Monday after the race and discuss how to proceed. Then we will know more about both of them.
"The good thing is that we have a strong squad. Liam Lawson is certainly at the top of the list, but there is also Isack Hadjar and Ayumu Iwasa."