Helmut Marko believes that Max Verstappen's promotion to Red Bull marked the "crunch point" for Daniel Ricciardo and his future at the team.
Ricciardo established himself as Red Bull's lead driver by outscoring Sebastian Vettel in 2014, after which the four-time World Champion left for Ferrari.
However, replacement Daniil Kvyat had lasted just over a season alongside the Australian when Red Bull opted to put the highly-rated Verstappen in the senior outfit.
From there, the Dutchman strengthened his position within the team and raised eyebrows in the paddock by signing a lucrative new deal in 2017.
At the end of the following season, Ricciardo opted to leave Red Bull for a new chapter at Renault.
Marko shares his assessment of Ricciardo
Looking back on Ricciardo's Red Bull career, Marko explained that he was quick from the outset.
"A cheerful, natural talent with outstanding car control," declared Marko in an interview with The Red Bulletin.
"I remember at the very first selection, he came out of the final bend with the back of the car way out, but he managed to get it back under control and even ended up making some time.
"Daniel gets into the car and is fast straight from the off.
"Even before he came to Red Bull Racing, his career was on an upward trajectory the whole time.
"In his first year at Red Bull Racing, he beat Vettel by three wins to nil."
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Verstappen's promotion is a turning point
According to Marko, Verstappen's quick ascent from Toro Rosso to Red Bull marked the beginning of the end for Ricciardo.
"Max coming on the scene was a crunch point in his career," the Red Bull advisor continued.
"Rather than taking up the fight, he wanted to keep his distance. And you know what happened next. That's too bad!
"He was always nice to work with. His speed is comparable to Max, but he's just lacking that ultimate consistency."
Ricciardo spent two seasons with Renault before making the switch to current team McLaren.
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