Prominent Perth trainer-reinsman Shannon Suvaljko faces a Racing and Wagering WA stewards' inquiry into five-year-old pacer Love In The Dark's elevated total carbon dioxide at Pinjarra on April 21.
RWWA's general manager of racing integrity Denis Borovica said the mare had a TCO2 level exceeding 36 millimoles per litre in plasma before she ran unplaced in the $20,000 Golden Girls Mile (1684m).
The high level had been detected by Perth's ChemCentre in a blood sample and was verified by the Racing Analytical Service Limited Laboratory in Victoria.
Suvaljko, who has been asked to attend an inquiry on May 12, has driven more than 80 winners this season.
Stewards have twice disqualified Suvaljko and also hit him with a $5000 fine.
He was banned for 12 months after Viking Hanover tested positive to dexamethasone in 1994.
Suvaljko copped a $5000 fine after Justforaninterest returned an elevated TCO2 level in 2004.
Stewards gave Suvaljko another 12-month disqualification when After The Rain was found to have a high TCO2 reading in 2005.
·Meanwhile, a smart work-out yesterday convinced Bunbury trainer John Graham to run unbeaten two-year-old Persistent Threat in Friday night's $50,000 Champagne Classic (2130m) at Gloucester Park.
The youngster, heading to his sixth start, is showing no after- effects of a record-breaking win in last Friday's $100,000 WA Sales Colts and Geldings Classic (1730m).
"He looks up to the task of winning twice in a week," Graham said.
"I can't fault him on the track. He's also come through well from swimming exercise."