Mat Coch writes:

With just one test remaining before the season gets underway in Australia in three weeks time there remains concern over the speed with which the new Pirelli tyres are degrading. Pitpass revealed during the opening test in Valencia that tyre degradation was excessive, one correspondent amongst the inner sanctum suggesting "this is beyond degradation, this is destruction".

While many have taken high tyre wear to mean better racing there are others who are less convinced. Ferrari's Fernando Alonso has suggested the high wear rate and need for frequent pit stops will hurt the leading teams, while world champion Sebastian Vettel seems resigned to the fact he'll be heading to the pits at least three times a race. In Melbourne that equates to a stop every fourteen laps or so while at longer circuits such as Spa-Francorchamps it could see drivers pitting every ten laps.

That's of course assuming Vettel is correct, though there seems no reason to believe otherwise considering one leading team is splitting the tyre's side walls. At the last test in Barcelona tyres were degrading to such an extent circuit officials swept the circuit twice a day, once during the compulsory lunch break and again at night.

In Jerez pieces of tyre were retrieved not only from the roofs of the teams pit stands but high on the gantry which straddles the pit straight. In Barcelona rubber was found on access roads beyond the existing catch fencing designed to keep spectators safe from potential danger.

Marbles, which have been a feature of all pre-season tests so far, aren't new or even uncommon, but what is unusual is that even the straights were littered with them. Typically marbles are limited to the outside of corners, where the lateral load on the tyre rolls balls of rubber off their surface. That straights are littered with rubber is something altogether new.

More worrying still is the size of some of the marbles. Some have been so large the term 'marble' fails to adequately describe them, necessitating a new term, perhaps 'super marble'.

The sheer size of a super marble would suggest that rubber is building up on the cars before breaking free in larger clumps, some the size of an adult hand. One such super marble was retrieved from the main straight during the most recent test in Barcelona, Pitpass carrying images which clearly showed its unusual size and consistency.

Several cars have already fallen foul of these super marbles with wings and sidepods taking a battering, drivers frequently returning to the pits with their pristine paintwork caked in and battered by the Pirelli rubber.

If super marbles are capable of damaging cars one has to wonder what affect they could have on an individual, especially when Formula One reaches circuits such as Monaco or Singapore where fans are able to get much closer to the track.

It's also not inconceivable that a lump of tyre could be thrown from a car and strike another driver, in a similar manner to the way Felipe Massa's 2009 season ended when he was struck by a spring from Rubens Barrichello's Brawn. Such an occurrence would seem to be incredibly bad luck, but then again serious accidents usually are.