Smolda was displaced by Ideal Scott as favourite for the 3yr-old pacer division of the Harness Jewels after he faded to sixth on Friday night.
Harness Racing New Zealand stewards subsequently contacted trainer Mark Purdon about the condition of Smolda. Purdon said the horse had been scoped by a veterinarian and found to be incubating a respiratory infection. Treatment commenced on Saturday. Purdon said he would inform stewards of the result of a blood test from Smolda.
Smolda is a $3.50 second favourite in final field betting behind Ideal Scott ($2.40).
Donaldson, who is in the 4yr-old trotter section of the HJ, has been treated for a muscular disorder and hock soreness since he last raced. Stewards sought information on Donaldson from co-trainer Greg Hope after the gelding ran on strongly to win a workout at Cambridge on Sunday, the last 800m in 57.9.
Donaldson finished second-last in a field of 14 at Cambridge at his last start on May 17. He had finished second to Phil's Gift there at his previous start.
Donaldson is at $31 in final field betting.
• Stirling Point is back in the Clevedon stable of Barry Purdon. Stirling Point had two starts in Southland in January for a fourth from the Winton stable of Allan Beck, who prepared the gelding for his first three wins. Stirling Point, owned at Ryal Bush by Ben and Karen Calder, won four races, including the Thames Cup last winter, when trained by Purdon and Scott Phelan.
• Murray Gray, the Ryal Bush trainer, died suddenly on Sunday at the age of 63. Gray had good success as a trainer with Giovanetto and Jaccka Jack.
He bred and raced Giovanetto (Fitch-Bella Ragazza), winner of 18 races, including the 1991 NZ Welcome Stakes, Pacifica Shipping and Monsanto Free-For-Alls at Addington. Gray also bred and developed the top pacer Holmes D G, a half brother to Giovanetto.
Holmes D G was sold to patrons of the Barry Purdon stable after finishing second to Enter Hurry Zone in his lone start as a 2yr-old at Forbury Park in 1997.
Jaccka Jack has won 12 races and $123,000.
Members of the Gray stable have been transferred to his son, Brett.
