Ricciardo had begun the year with victories in China and Monaco, putting him in the mix for the title fight with Lewis Hamilton and Sebastian Vettel.
But he has not appeared on the podium since his victory in Monte Carlo in May, having suffered a number of mechanical issues with his car.
The Australian had four retirements in the space of six races from July to September as his season continued to spiral out of control.
Max Verstappen too has had his fair share of issues in 2018, retiring four times overall.
But the Dutchman has finished on the podium four times in his previous six races, further highlighting the difference between the two Red Bulls of late.
The contrast was even greater last time out at the US Grand Prix when Ricciardo was forced to pull up on the ninth lap.
Meanwhile, Verstappen battled from 18th on the grid to finish second in a spectacular drive.
And Red Bull chief Christian Horner has revealed Ricciardo’s temperament got the better of him when he returned to the team garage.
“It’s a crying shame for Daniel, I feel so sorry for him,” Horner said.
“It looks identical to the power unit issue he had in Bahrain where it’s just gone into complete shutdown – you could see it mid-corner.
“He was driving a strong grand prix and would have been right there too.
“It’s so frustrating for him.
“He’s taken out his frustration in his room by putting his fist through the wall which you can totally relate to.”
He added: “It turned out to be exactly the same failure as in Bahrain earlier in the year where it looks like a major issue in the Energy Store.
“It just takes out all the power. We’ve got another Energy Store within the allocation without having to take a penalty.
“The Renault guys in the garage apologised, which we appreciate, but the frustration is for Daniel.”