Promising Sydney sprinter Tonsor keeps passing each new test but faces a career-defining race at Eagle Farm.

Tonsor made short work of an Open Handicap over 1350m at Doomben last Saturday week at his first Brisbane start.

It took his record to five wins and three minor placings from eight starts.

Trainer Matthew Smith sent Tonsor north to find a suitable distance for the gelding and to get a guide to him in open company.

Smith will get a far better idea of Tonsor's place in the pecking order in Saturday's Sporting Chance Foundation Open (1400m).

The field includes five stakes winners and several others who have been placed in black-type races.

Smith realises Saturday's race is a far tougher test for Tonsor but he welcomes the challenge.

He said Tonsor would have to perform to justify any talk of being a winter carnival horse.

"The thing is for him to learn not to go too hard. He can want to over-race so it is a learning curve," Smith said.

He believes there are plenty of options if Tonsor can continue to improve.

"The Doomben race was a chance to give him a first test. But now he is in form it is time to a bit higher.," he said.

"If he shows he could be a stakes horse a race like the (Group Three) BRC Sprint over 1350 metres at Doomben might suit him.

"Then he might go higher or come back s bit. But we should have a better idea after Saturday."

There are few better bred horses racing in Brisbane than Tonsor who is by the late super sire Redoute's Choice out of VRC Oaks winner Egyptian Pulse.

"He does have the bloodlines and it is obviously a plus he is starting to live up to them.," Smith said.

Tonsor had barrier one at Doomben and has drawn the two gate this week.

"I thought Murphy's Law would prevail and we would get barrier 18 but to get two is ideal for his racing style," Smith said.

Robbie Fradd rode Tonsor at Doomben and is a big fan of the horse.

"I think he is definitely a stakes horse but I suggested they tried him at 1400 metres to see if he might even be something a bit better," Fradd said.

Smith also nominated Summer Cup winner Fierce Impact for the Open handicap but did not accept.

Fierce Impact is likely to head north next month for the winter staying races.