Riding charges have been laid against apprentice Tom Sadler and jockey Craig Robertson.

Racing Victoria stewards issued one charge against Sadler and two charges against Robertson on Wednesday.

Sadler's charge stems from his ride on Lonrockstar in the Brett And Mark Wilson Sprint at Caulfield last Saturday.

Lonrockstar, trained by Sadler's father John, finished 11th as a $6 second favourite after being last to the home turn.

Stewards allege Sadler didn't take all reasonable and permissible measures throughout the race to ensure Lonrockstar obtain the best possible finishing position.

Robertson was charged after stewards allege he didn't allow Bolshoi Bandit to run on its merits when finishing last in a race at Echuca on April 10 when a $4.40 second favourite.

Stewards allege in his second charge that he didn't take all reasonable and permissible measures throughout the race to ensure Bolshoi Bandit obtain the best possible finishing position.

The second charge against Robertson was issued should the first charge could not be sustained.

Robertson and Sadler will front the Racing Appeals and Disciplinary Board at a date to be fixed.