Alonso expects Mercedes slump to remain a "mystery"

The way that Mercedes struggled for pace last weekend on the back of its season-long dominance left many in the sport scratching their heads, and even prompted wild theories of the team being deliberately hobbled.

But while the Brackley-based team thinks it has discovered the answers in terms of tyre temperature issues, Alonso suggests that the full reasons may never come to light.

He is confident, however, that it will prove to be a one-off, and Mercedes will be back on form in Japan.

"I think I will be surprised if this [Singapore performance] will be the normal performance of Mercedes," he explained.

"We have all been here many years, and we never saw [any team] being one second faster all year long and being 1.5 seconds slower for another race.

"This is a mystery that we will probably never understand. But this is F1. You take it or you leave it."

Pirelli explains tyre picking process

Pirelli found itself in Singapore having to deny suggestions that there could have been a conspiracy involving Mercedes running different compound tyres to everyone else.

In a note sent out to media on Thursday, Pirelli explained how F1's tyre picking process worked to make clear that such a scenario could not happen, because selections are totally random.

This means it would have been impossible for it, or anyone else, to have deliberately influenced the tyre selection to give one team either superior or inferior rubber.

All of the 1700 tyres that are used over a GP weekend are fitted with a bar code, which is embedded in the structure and cannot be removed.

Pirelli's system then randomly grounds the bar codes in to blocks of four – for two front and two rear tyres – and then a list of those sets is sent to the FIA.

The FIA then allocates those sets to teams on a random basis.

The Pirelli note said: "Pirelli itself is not involved in this whole process at all, meaning that the Italian firm cannot if any way influence which tyres are allocated to which teams, or when they are used – although a rigorous quality control process ensures that all the tyres leaving the factory are identical anyway."

Pirelli motorsport director Paul Hembery added: "Deciding which tyres are allocated to which teams, or when they are used, is a job taken care of entirely by the FIA once the tyres have left the factory."