A US-bred gelding that did his early racing in the UK, Buffalo River will run on Saturday in the Listed Weekend Hussler (1400m) at Caulfield.
Moroney said Saturday's race would determine Buffalo River's spring path.
Buffalo River resumed from a spell in the Group 1 Sir Rupert Clarke Stakes (1400m) at Caulfield on September 18, finishing 10th behind Sierra Sue, beaten just over 3-½ lengths after leading.
The gelding can be his own worst enemy in his races by over-racing and Moroney has called on Damien Oliver to again partner the gelding.
Oliver rode Buffalo River to win his first three starts on Australian soil along with his most recent victory at Sandown, on heavy ground, at Sandown in May last year.
The last time Oliver rode Buffalo River was when second over Saturday's course and distance when resuming in September last year.
"He is a little bit behind, but we thought we might chase some Country Cups over a mile with him rather than having a go at the Group 1's," Moroney said.
"But if he happened to win, we might change our mind.
"His crossroad will be this start. We've decided to go a little bit weaker but we're getting Ollie back on and we're hoping he'll be able to assess him and give us an idea of where we're going."
While Moroney is trying to race Buffalo River back into form, the spring is over for high-priced European import English King who is going to be gelded.
"As soon as the sprint went on, and I know it was The Valley, but the rider said when he asked him to go, he just didn't want any part of it," Moroney said.