RACING NSW stewards went behind closed doors when the name of Melbourne underworld boss Paul Sequenzia was brought into evidence in the Sam Kavanagh cobalt inquiry.

CHRIS ROOTS reports for FAIRFAX MEDIA that Adam Matthews, who spoke to the stewards by phone from Greece, had denied having any part in organising race-day treatments for Kavanagh, who is facing charges after Midsummer Sun returned a swab with cobalt and caffeine levels above the threshold after winning the Gosford Cup in January.

Matthews did admit supplying Kavanagh with 10 yoghurt drenches for $750 in late 2014.

Chris Wenneke, acting for Matthews' former boss at Flemington Equine Clinic Tom Brennan, turned the focus on the vet's associations with John Camilleri, who has also been charged in the case, then Sequenzia.

Matthews was asked about his betting accounts, in particular his wife's TAB account, before stewards decided the inquiry should be heard in camera because it related to financial matters.

Stood-down trainer Kavanagh and Brennan unsuccessfully argued cobalt wasn't a prohibited substance.

Kavanagh pleaded guilty to presenting Midsummer Sun with a level of cobalt above the threshold when he won the Gosford Cup last January. He pleaded not guilty six charges relating to administrating cobalt to his horses and reserving his plea on another charge of having four substances not labelled in compliance with relevant state and federal legislation.

Brennan pleaded not guilty to 10 charges related to cobalt but guilty to supplying the bottle of vitamin complex, which was found to a level of cobalt up to 175 times that of a registered products. He pleaded guilty to giving false and misleading evidence to stewards.

Wenneke was asked by Keith Mason QC if the panel should take into account the conduct of his client after the Midsummer Sun swab in that he changed his evidence. 

"It has just been exercising my mind," Mason said.

Wenneke opened the day by having an attempt to the inquiry adjourned for up to eight weeks rejected. He argued cobalt was not a prohibited substance under the definition in the rules of racing, even though it is on the WADA prohibited substance list.

He asked Racing NSW vet Craig Suann if cobalt had an effect on the blood system. Kavanagh also argued cobalt did not have the effect of raising red blood cells as would be expected if the drug had an EPO effect.

Wenneke based his argument for cobalt not being a prohibited substance on one paper, H.K.Knych's "Pharmacokinetics and selected pharmacodynamics of cobalt following a single intravenous administration to horses", which was released in July last year.

Kavanagh presented blood pictures from Midsummer Sun taken before his first Gosford Cup win in 2014 through a 12-month period, some of which were when he admitted using the cobalt treatment. It showed no significant change in the red blood cell count up until his win in the same race, where he tested positive to cobalt, 12 months later.

Kavanagh had Suann admit the red cell count had not shown significant change from early morning blood pictures taken routinely by the stable during the 12 months. 

"This is all about science and you cannot leap over that science," Wenneke summarised the argument. "You are simply not able to say the substance affects the blood of a horse."​​

After considering the submission, chief steward Ray Murrihy said his panel was satisfied cobalt was a prohibited substance. 

The inquiry continues on Tuesday.