Sam Clipperton is set to apply for an extension on his apprenticeship to help him outride his city allowance as well as clinch a sought-after premiership title.

Clipperton, who has made the running in the Sydney apprentices' premiership for most of 2013-2014, comes out of his time on July 15.

But his master, Randwick trainer Ron Quinton, would like to see the 20-year-old wait until the start of the new racing season before joining the ranks of Sydney's senior riders.

Clipperton needs another six metropolitan winners to outride his 1.5kg claim and he could easily take a step closer to the milestone with a solid book at Warwick Farm on Wednesday.

"Sam comes out of his time in the middle of July but we are thinking about getting an extension for him," Quinton said.

"I haven't ruled that out just yet.

"He's still got a claim and he hasn't got that many wins to go and in one way it would be lovely for him to outride his allowance."

Quinton said the start of a new Australian racing season on August 1 would also be an appropriate time for Clipperton to become a senior jockey.

"An extension will also give him another two weeks to the end of the racing season as well and I think it would be a great idea for him to do that," he said.

Quinton will supply one of Clipperton's better rides at Warwick Farm in consistent middle-distance campaigner Mr Scary.

Clipperton's 1.5kg claim will bring Mr Scary into the Instagram@atc Races Handicap (1600m) with 58.5kg after a promising return to racing when midfield to Generalife at Rosehill.

"He's a wet tracker and once he gets in form he's a very consistent horse," Quinton said.

Clipperton has ridden 19 metropolitan winners this season and is five head of Serg Lisnyy in the race for Sydney apprentices' title.