No big deal about making a mess. That's racing....would've been much worse without the diaper.
Did you assemble it yourself or have someone else do it? Definately look for black bearings like doorracer suggested and/or black rod big ends. Since it was fresh, it's probably a clearance or assembly issue such as rod caps swapped, bolt torque, or if it had h-series bearings, swapped bearing halves. The h series rod bearings have a large chamfer on one side, so there is an upper and lower half. Could also have been a rod bolt failure or a number of other things....
Later,
Johnny