Verstappen, 20, has stood on the podium only once in the six races so far in 2018 and has had two retirements, while Australian team-mate Daniel Ricciardo has won twice. The youngster has also drawn plenty of comment and criticism for his errors.
“We’re all human,” Newey said. “He can try and shrug off everybody else’s comments and opinions but when you’ve had a run like that, you question yourself a bit. Of course you do.
"But I think he’s tough enough that he’ll come through that,” added Newey. “He’s had one of those bad runs. He’s a great driver, he’s very quick and at some point he’ll shed that again and be on his way. Part of being a racing driver is learning from your mistakes and he’s bright enough to do that.”
'Everything keeps going wrong'
Former world champion Nico Rosberg said after Monaco, where Verstappen crashed in final practice and lined up last, that he had not seemed to learn at all despite being in his fourth season.
“At the moment everything is going wrong for him but I don’t have much hope for him anymore,” Rosberg said.
Team principal Christian Horner said after the Monaco crash that Verstappen knew he had to cut out the mistakes.
“He needs to learn from it, and stop making these errors," Horner said. "He knows that more than anybody - for the whole team to only be running one-legged with such a strong car is frustrating.”
Verstappen finished third in Spain in May but retired in Azerbaijan after a collision with Ricciardo. In China he tangled with Mercedes’s Lewis Hamilton and Ferrari’s Sebastian Vettel, ending up fifth. He also collided with Hamilton in Bahrain and retired, while in Australia he spun and finished sixth after starting fourth - but he will be Red Bull’s main hope at this weekend’s Canadian Grand Prix.