Adelaide trainer Gordon Richards has no qualms about extending Benz to the distance of the Sandown Guineas.

At Sandown on Saturday Benz will be attempting 1600 metres for the first time.

Richards has always thought highly of Benz's ability and was planning a Caulfield Guineas assault until the gelding had a minor setback.

Benz is yet to race beyond 1400m, a trip he ran fifth over at Flemington last Saturday after jumping from barrier 16.

"There's never been any need to put him over a mile as he was winning over the 1000 and 1200 metres without any problem," Richards said.

"When he ran such a good race last week over 1400 and while we were in Melbourne we thought we could stay over and put him in this race.

"I've never had any doubt about him running it (1600m) but having said that if he gets any daylight he tends to get going a bit."

Richards said Benz was keen in his last-start fifth behind Souchez after drawing wide.

However the trainer took heart from his previous outing when fifth in the Listed Durbridge Stakes (1200m) at Morphettville on October 15.

He said the gelding was slow into stride and raced towards the tail, but importantly settled well.

Richards doesn't see the Sandown Guineas as being an overly strong race.

"Morton's Fork and Jennifer Lynn are possibly the two strongest horses but the rest look pretty even," he said.

"My horse, he's a trier, and if he puts in again he'll be around the mark."

Benz sits on the third line of betting at $7.50 with Morton's Fork a dominant $2.05 favourite ahead of Jennifer Lynn at $4.