Riverina trainer Norm Diebert Snr must have achieved some sort of record as the oldest trainer ever to have a horse throw a positive to cobalt, after the substance above the threshold of 100 micrograms per litre in urine was detected in the urine sample taken from his pacer CHANCETOWIN following its win in race 4, the RIVERINA SIGNMAKERS PACE (1740 metres) conducted at Wagga on Friday 15 May 2026.