Wolff doesn’t know if Red Bull has fallen back, but he does know that the gap has clearly narrowed

Mercedes boss Toto Wolff isn’t sure if Red Bull have taken a step back against their rivals despite admitting the gap at the top has narrowed.

Red Bull’s dominance under the current ground effect regulations continued last season as Max Verstappen dominated unchallenged to record an incredible 19 wins, with Red Bull only stopping Ferrari from taking all the wins for the season.

However, the three-time champion and Red Bull have been beaten in two of the previous four races, and his two wins in Imola and Montreal have come against intense competition.

The convergence of the grid in this term led to the revelation of Red Bull’s weaknesses as the problems with driving on the curbs came to light and made them worse.

Mercedes technical director James Allison said Red Bull’s upgrades appear to have been “downgrading” – a view denied by Christian Horner on two occasions.

While he would disagree with his colleague’s comments, Wolff accepted the positive side that the battle at the top end is becoming more competitive.

“The last few races have been more difficult for them [Red Bull],” Wolff told Sky F1. “Everybody made good strides [towards] forward.”

“There were two or three teams that could have potentially won the race [in Canada], maybe not us.”

“I don’t know if [Red Bull] took a step back. The most important thing is that [the backlog] is decreasing,” he pointed out.

Along with Ferrari and McLaren, Mercedes have made enough inroads over the past few weeks, resulting in pole position and a podium finish for George Russell in Canada.

But while Mercedes seems to have figured out its redesigned W15, Wolff is cautious about whether their pace will translate to conventional tracks.

“I hope [the performance in Canada] is not related to the track,” he added. “Montreal is out with that medium cornering speed and change of direction.”

“In general, the drivers said that the car is now in a space where they can push it, that they have more confidence and that everything goes much, much easier.”

Meanwhile, Wolff expects Red Bull to return to full form at the upcoming Spanish Grand Prix, which he believes “will be a good test because there are all kinds of turns.”

“Maybe Barcelona will be interesting, regardless of whether you are strong there,” he explains.

“Austria is their territory. McLaren were strong there last year when they came back. That’s never good for us.”

“You can’t ignore Max and Red Bull, they’re still the benchmark, they’re up there.”

“But McLaren has made great strides, and don’t forget Ferrari, they weren’t visible [in Canada], but two weeks ago [in Monaco] they were the benchmark.”

“These are four teams that are competitive now,” added the Mercedes boss.