Renault's Formula 1 power unit struggles are having a two-fold impact on Red Bull, according to Daniel Ricciardo, compromising its set-up.
Despite Mercedes' clear power unit advantage in 2014, Ricciardo won three grands prix, with the team's RB10 good enough to recover some of the shortfall and be best of the rest.
However, Renault has fallen further behind both Mercedes and Ferrari this year and Red Bull has slipped to a distant fourth in the constructors' championship.
With a fourth-place finish for Danill Kvyat in Monaco its best result, the team has also been shown up on several occasions by sister squad Toro Rosso, which is equipped with the same power unit.
"This year we've struggled a bit more in braking, I don't think we've had as much feeling with the car under braking," Ricciardo said.
"I would say we've got some of that back, so that's coming, and I think a lot of it's rear grip, to be honest.
"I think it starts with traction, but [corner] entries, every driver will say the same - you can never have enough.
"Even when I watch onboards of the Mercedes, they still have some slides here and there."
In Red Bull's case, though, the search for rear grip has been hindered by having to trim downforce from the RB11 to compensate for Renault's lack of horsepower.
"A lot of the stuff comes back I guess to compromising for loss of power," Ricciardo said.
"In a debrief we'll complain the car is sliding and we can't get it to turn in here or there, and we're just not able to run as much downforce with the loss of power.
"Maybe we feel the car isn't great in some areas, but I don't feel we're running it at its optimum level.
"Monaco was really the first place we could bolt everything on it, and it was our most competitive race."
HUNGARY A 'BETTER OPPORTUNITY'
A new front wing led Red Bull's chassis upgrades at Silverstone, helping it regain ground on Ferrari and Williams, and while Ricciardo retired early with an ERS and turbo failure, Kvyat took sixth.
Team principal Christian Horner, who felt the Russian could have challenged for a podium if not for a spin, declared it a positive step heading to Hungary, where Ricciardo won last year.
"We take heart from this weekend," he said post-race.
"It's been an encouraging step, throughout practice and the grand prix we have looked certainly lot more competitive and Hungary represents a better opportunity for us."