Did tighter tyre rules hurt Mercedes?

I think the Formula 1 world was a bit shocked in Singapore. How could the dominant Mercedes team drop the ball so badly?

Was it just circuit-specific, was it because of the temperature, was it the number of slow-speed corners or was it just that even Mercedes is only human and can get it wrong just as easily as anyone else?

For me the big question is: was it that everyone else got the set-up in Singapore right and Mercedes got it wrong, or could there have been another reason?

To try to get an answer to these questions we need to look at a few more detailed facts and crunch some numbers.

Taking the qualifying performance of the fastest Mercedes, Ferrari and Williams so far this season, we get the following percentage gap taken from the Q3 sessions.

(I haven't counted Williams in Monaco since it had a terrible weekend and didn't make it into Q3. On the one occasion this year that Mercedes hasn't been fastest, I have still used it as the reference point for clarity).

Australia (soft tyres)
Mercedes 0.000 - Ferrari +1.639%, Williams +1.611%

Malaysia (medium tyres - comparison from Q2)
Mercedes 0.000 - Ferrari +0.251%, Williams +1.176%

China (soft tyres)
Mercedes 0.000 - Ferrari +0.945%, Williams +1.224%

Bahrain (soft tyres)
Mercedes 0.000 - Ferrari +0.444%, Williams +0.875%

Spain (medium tyres)
Mercedes 0.000 - Ferrari +0.918%, Williams +1.196%

Monaco (super-soft tyres)
Mercedes 0.000 - Ferrari +1.000%

Mercedes has normally been pacesetter © LAT

Canada (super-soft tyres)
Mercedes 0.000 - Ferrari +0.835%, Williams +0.953%

Austria (super-soft tyres)
Mercedes 0.000 - Ferrari +0.519%, Williams +1.077%

Britain (medium tyres)
Mercedes 0.000 - Ferrari +1.226%, Williams +0.907%

Hungary (soft tyres)
Mercedes 0.000 - Ferrari +0.877%, Williams +1.465%

Belgium (soft tyres)
Mercedes 0.000 - Ferrari +1.459%, Williams +1.250%

Monza (soft tyres)
Mercedes 0.000 - Ferrari +0.297%, Williams +0.668%

Singapore (super-soft tyres)
Mercedes 0.000 - Ferrari -1.362%, Williams +0.362%

I've included Williams as it's generally been the second-fastest Mercedes-engined team and has had at least one car in Q3 everywhere except Monaco. It gives us a reference for power unit performance and a way to measure whether Nico Rosberg's failure at Monza meant Mercedes had to alter the performance on its works cars for reliability reasons.

Leading up to Singapore, everything pointed to Mercedes having a car for all occasions. It seemed to be on top of the set-up for all the different tyre compounds. Whether it was hot, cold, wet or windy, it appeared able to cope with it.

Ferrari and Vettel were unbeatable in Singapore © XPB

That all stopped in Singapore, where its fastest car was 1.362 per cent slower than the fastest Ferrari after being 0.868 per cent quicker than the average of the two Ferraris' Monza Q3 pace. A switch of 2.224 per cent in F1 terms is like the light switch has just gone off.

I can understand that on a bad day you might lose out by one per cent - as we have seen with Ferrari on occasion over the season - but to double that plus is like the engineering staff just didn't turn up.

Lewis Hamilton was faster than Roserg by his normal couple of tenths of a second in Singapore, and at a 0.362 per cent deficit Williams was closer to Mercedes than its Monza average of 1.127 per cent across both cars.

So taking that all into account, it looks like Mercedes was just having a weekend off and being nice guys in keeping the championship alive...

Obviously it wasn't quite as simple as that. If we look at the races after Spa, when Pirelli and the FIA put into action control over minimum tyre pressures and maximum tyre temperatures, I think we see a slight trend.

Ferrari's average deficit to Mercedes pre-Monza was +0.919 per cent, Williams's was +1.173 per cent.

Ferrari's average over the last two races -0.532 per cent, Williams +0.515 per cent, so a major swing in performance that definitely could not have been predicted pre-Monza.

How could tyre pressures affect this?

The temperature and pressure of the tyres go hand in hand, and that is why Pirelli has instigated control over both. It's only really interested in forcing the teams to use higher pressures, or at least a minimum tyre pressure.

If the pressure is too low when the tyre is heavily loaded, it can damage the structure of the carcass - which can lead to a tyre failure.

Pirelli and the FIA have tightened procedures © LAT

We know that when Mercedes' tyre pressures were checked on the grid at Monza they were lower than the Pirelli requirement, while Ferrari's were OK.

It was decided that the pressure checks were a bit random and that tighter and better control was necessary before any action could be taken, so in Singapore that was what was done.

When you fit a new set of tyres for qualifying - especially of the softest compound, which is the highest-grip tyre and what was used Singapore - the normal problem is getting the front tyres to work in balance with the rear tyres.

If this doesn't happen, the teams tend to increase the front tyre temperatures.

This helps the drivers' feeling when they leave the pits, but in reality all you have done is harden the compound of the front tyre that few per cent so ultimately you have less grip.

So the other option is to reduce the temperature of the rears. But as I said earlier, the temperature and pressure go hand in hand - so reduce the temperature of the rears and the pressure will also reduce to below the minimum required by Pirelli. That meant for Monza and especially Singapore this set-up direction was a no-no.

Mercedes is also the team that on many occasions this year would do two warm-up laps on new tyres before putting in a qualifying lap.

If you have had a handle on a set-up that has worked all season with specific front and rear tyre pressures, and suddenly a curve-ball is thrown in such as a minimum tyre pressure requirement, it will undoubtedly change how you have to think and react to the situation.

Will it be the same in Japan? For the championship's sake we can only hope so.

For sure in the short gap between Singapore and Japan there will have been a lot of head-scratching in Brackley.