Today Pirelli have announced that they will attempt to make the 'marbles' on the track reduced or at least smaller than they are currently after the drivers reported that the marbles were starting to make overtaking quite hard because of the marbles being scattered all across the track. Pirelli though have been tasking with creating tires that will bring back racing to the racers. This has been done by making the tires degrade quicker but because of this the the marbles have been coming off nearly twice the size than that of bridgestone's and they've been coming off quick. The marbles are not new to the sport though, as the marbles are the main part of tire degradation which do then make the pit stops. 

More as we get it and don't forget that the China Grand Prix Practice 1 & 2 is tomorrow from 3:00 am GMT + 0