"We want to try to run him before Boxing Day or New Year's Day and this looked a good race to kick him off in," said Phelan, who trains in partnership with his father, Craig.
"We want to try to qualify him for the Karaka Million 3YO anyway. After Monday, we could look at the Uncle Remus [1400m Listed race at Ellerslie on Boxing Day] or the one on New Year's Day [Group 2 Auckland Guineas over 1600m] but that might be a hard step going straight to the mile."
After returning to Cambridge, Riverplate had a fortnight in the paddock at Ross MacKay's Ohaupo agistment farm Leanach Lodge. MacKay and his father, respected Cambridge equine veterinarian Ross MacKay, are co-owners of the colt.
"Ian ran the ruler over him and gave him the all-clear to return to work. He's a really laid-back, straightforward horse. He's got a lovely action and he's working well," Phelan said.
"We broke him in and he had one start for Andrew and ran second to Mustang Valley. His form in Australia wasn't too bad. He ran into a bit of bad luck a few times in those good races but they thought enough of him to have a go at the Caulfield Guineas.
"His first run over 1200m over there was pretty impressive so we thought we'd like to try him over 1200m here first anyway. We're not too sure what to expect but on his form so far, you'd think he could go close to winning that, especially with the ambitions we've got."
Riverplate holds nominations for the Group 1 New Zealand Derby (2400m) at Ellerslie on March 5 and the Group 1 Levin Classic (1600m) at Trentham on March 19.
Also at Te Rapa, Tannahill will have his final leadup to the 1500 Championship Final at Ellerslie on Boxing Day.
"If we can get into that, it looks a good race for him. He's going well," Phelan said.
Among other Christmas racing targets for the Phelan stable is the Group1 Railway (1200m) at Ellerslie on New Year's Day with recent acquisition Dawn Patrol.
"He went a good race last week and we'll look at the Railway and maybe the Telegraph with him."
●The Ashburton races scheduled for today have been postponed until next Tuesday because of water pooling on the track yesterday.
NZ Racing Desk