In the main event, the 4-9-litre Bugattis driven by Czaykowski and Varzi immediately took the lead, with Varzi's car barely a length astern. Lap after lap the two Bugattis held close station, each driver encroaching more and more into his braking distance at the end of the long straights, in an attempt to gain even a few yards. Lap by lap the record was broken; both cars, so close were they together, were credited with a lap speed of 128.5 m,p.h. on lap 9; next time round both cars reached 130; next time, 132. In overtaking Czaykowski on the 14th lap, Varzi recorded a speed of over 136 m.p.h., and on the 15th and last lap the two blue cars set off almost side by side.Down the long straight they ran, flat. out, with Czaykowski trying time and again to pull out of Varzi's slipstream and reverse the positions. At the end of the straight the Polish driver outbraked Varzi and managed to get alongside, but there was not room to get past in the corner.
On the exit from the corner the cars set off nose to tail and, as they thundered up towards the stands, with the bright sun glinting on the roofs, Czaykowski changed up into third a shade before Varzi. It seemed to give him a slight advantage, and the front wheels moved up alongside the leading car. From the corner of his eye Varzi saw the bonnet thrust forward inexorably - inch by inch. He could do nothing at all about it but sit . . . and watch. . . and hope.Suddenly they were at the flag-not quite hub-to-hub. The officials gave the race to Varzi - by half a wheel.