Explained: Mercedes wing experiments influenced Hamilton’s deficit to Russell

Russell ended FP2 with the ninth-quickest time, some eight tenths adrift of pacesetter Carlos Sainz, while Hamilton was only 17th, 1.428 seconds off the pace. 

The seven-time world champion was one of only two drivers (the other being Lance Stroll, whose Aston Martin broke down) not to complete a soft tyre run, which accounted for some of his deficit. 

Mercedes communication director Bradley Lord revealed during Sky F1’s coverage that the team had changed the wing level on Hamilton’s car in the break between practice sessions. 

This was to compare performance as Mercedes seek to optimise their W14 challenger for the unique layout of the high-speed Monza circuit. 

Hamilton appeared puzzled about his losses in a straight-line, and saw a request to make changes to his car during the session rebuffed by race engineer Peter ‘Bono’ Bonnington. 

Here’s how it played out over team radio. 

LH: “How far am I down in the high-speed? The straight line.

Bono: "We are about 5kph down to George. A bit more than in the sim.” 

LH: “Where is six tenths coming from in the first sector? It's just two straights.”

Bono: "It's mainly straight line but there's a little bit of a loss turn one to turn two.”

LH: "I'd rather box and get this changed.”

Bono: "That would wipe out most of our programme, that's the problem Lewis.”

Hamilton said he was confident Mercedes will be able to get his car in a better place in time for qualifying. 

“It was pretty similar Friday to most Fridays,” he said. “It started pretty well in P1 and I was generally quite happy with the car and then we made changes. 

“Usually when you go into P2, can’t figure out more, but the car seems to be more of a challenge in P2. So we’re just going through the data now and I’m sure it’s something we can rectify overnight.”

Hamilton added: “We’ve got a thousand things we can change, it’s just [about] knowing what the real issues are, whether it’s mechanical, whether it’s tyre temp, aero balance, we are going to figure it out tonight.”

Mercedes trackside engineering director Andrew Shovlin admitted it had been a “messy day” for the team. 

“We've not got the car in a good place at the moment,” he explained. 

“That means we have a bit of work to do overnight to get the setup in the right place for the rest of the weekend.

"Single lap and long run both need work if we want to be competitive. There's not much else to say; we just need to get on with the job of sorting the car out.”