Mercedes doesn't know why Ferrari's Monza F1 speed edge disappeared

Ferrari has a slight power advantage currently, and its performance has been further boosted by an energy deployment characteristic that allows it to accelerate much better out of corners.

A speed edge in the early phase of straights prompted questions from Mercedes earlier this year about the legality of Ferrari's double battery system, but the FIA gave the Italian team the all clear.

After turning the tables on Ferrari in a thrilling race at Monza, Mercedes says one of its tasks is to understand why its cars were suddenly a match for Ferrari just a day after its rival held a clear advantage in the battle for pole.

Asked if the team knew why there was nothing separating Ferrari and Mercedes in top speeds in the race, Mercedes boss Toto Wolff said: "No, I don't understand it.

"The performance pattern has completely changed from yesterday to today [Sunday], and I haven't got an explanation yet.

"Maybe the clever people around Shov [Andrew Shovlin, chief race engineer] will know, but I think we just need to analyse it."

Wolff suspects part of the answer may come from Ferrari being able to run certain engine modes in qualifying that it does not have available in the race.

"It looks like the performance that they are able to deploy on one lap is maybe something they cannot replicate throughout the race," he said.

"I don't want to go any further because it could be read in another way that I am trying to find excuses, but they have certainly had a very, very good car [on Saturday] and a good car [on Sunday].

"But we haven't seen Sebastian [Vettel] perform in a car without any damage."

Wolff also suggested that some of the explanation behind Mercedes being able to take the fight to Ferrari a week after it was defeated in Belgium came from its own progress.

"I am very proud of the work the team have done, all the engine guys and the chassis guys from Spa to Monza," added Wolff.

"We have understood the car better [and] understood the tyres better.

"We have added some performance and, even if Saturday didn't show it because we couldn't qualify on pole, I felt that we've done some good work over the last couple of days.

"And I would have also said that if he hadn't have won."