The arrival of Daniel Ricciardo is an important piece of the puzzle as Renault pushes towards the front in F1, according to David Coulthard.

Since announcing his shock departure from Red Bull for 2019, Australian Ricciardo has struggled this year.

But Renault is still looking forward to having the grand prix winner on board.

"New driver, new motivation, new ways of thinking, new experiences," top official Alan Permane told Auto Motor und Sport.

"It doesn't mean we didn't like Carlos (Sainz). But a fresh wind is always good."

It is also good in the eyes of Ricciardo's 2019 teammate, Nico Hulkenberg.

"Daniel has won several grands prix. He is fast and motivated," said the German. "I have to do my homework, be fast and consistent.

"In that case I have always beaten my teammates," Hulkenberg insisted.

However, besides signing Ricciardo, Renault has a big role to play. Hulkenberg says Mercedes and Ferrari currently "have a lot more power in qualifying".

But he estimates the car as "60 per cent" of Renault's problem relative to the faster teams.

The team is busily ramping up its efforts at the Enstone base, targeting almost 800 employees by the end of 2019.

But Hulkenberg says the top teams have sped ahead of Renault this year.

"They have understood something that we are yet to understand. And we have to discover this mystery," he said.

Former F1 driver David Coulthard, though, tipped the French outfit to keep improving.

"It is a real factory team that is investing heavily," he told the Dutch publication Formule 1.

"Signing Daniel is a real letter of intent about what they want.

"Lewis Hamilton is the superstar, Max has his aggressive style and Vettel the German winning mentality. But Daniel absolutely belongs on that list," said Coulthard.