Trainer John Sadler has an eye on the future with new recruit Observational which is why he has chosen to run him in the Ballarat Cup.

Sadler is keen to test him at a distance and has opted to run him over 2200 metres at Ballarat on Saturday rather than the shorter Kilmore Cup (1600m) the following day.

"There's a query as to whether the horse can stay or not and one of the reasons why he is probably running in this race and not the Kilmore Cup is that for next time in, I just want to see exactly what his trip is," Sadler said.

"It's a little bit further and it has been suggested that maybe he's a better miler. But if he runs the trip, he'll run very well."

The imported Observational was formerly in the team of prominent owner Lloyd Williams before being sold privately and joining Sadler's Caulfield stable.

Last year's Bendigo Golden Mile winner made his debut for his new trainer during Melbourne Cup week at Flemington, finishing 10th but beaten less than four lengths in a 1600m benchmark race won by Boom Time.

"It was a good run. He didn't have a lot of luck," Sadler said.

Observational began his career in the UK before joining Williams' private trainerr Robert Hickmott at Macedon Lodge.

He won the Golden Mile at his Australian debut last year but has not won in nine starts since with his best result a close third in the Group Three Easter Cup (2000m) at Caulfield in March.

Sadler formerly trained for Williams and has had success with horses bought from that team, most notably with Linton who he trained to win the 2013 Group One Stradbroke Handicap.

Observational has barrier eight in a capacity field of 18 plus four emergencies and is at $15 with the Lee and Anthony Freedman-trained Cool Chap the $6.50 favourite.

Lidari, one of four runners for Darren Weir, is at $8.50 along with the Chris Waller-trained Lady Le Fay.

Waller won last year's Ballarat Cup with Junoob.