Trainer John Sadler faces a charge of improper conduct over the scratching of Observational from a race at Sandown.

Racing Victoria stewards issued the charge against Sadler for his alleged conduct before and after stewards ordered Observational's scratching from the Group Three Eclipse Stakes at Sandown on November 18.

Observational was withdrawn after an out-of-competition test the previous day returned a TC02 level of 36.4 mmol per litre of plasma with stewards concerned he may have been administered an alkalising agent within one clear day of the race.

Stewards allege comments made by Sadler to chairman of stewards Terry Bailey in telephone calls on the morning of the race and in person to Bailey and deputy chairman Robert Cram at Sandown on the day of the race constituted improper conduct.

A date for a hearing before the Racing Appeals and Disciplinary Board has yet to be set.

Stewards are continuing the inquiry that led to Observational's scratching.