Mike Moroney is sweating on emerging galloper Buffalo River gaining a start in the Group One Sir Rupert Clarke Stakes.

Buffalo River has a relatively low rating and the trainer has some concerns as to whether he can get a berth in the field with his benchmark.

If he does get into the 1400 metre race he will be ridden by Jye McNeil.

Moroney is certain to have one runner in the Caulfield feature on Saturday in former well-performed New Zealand galloper Harlech, who will be making his Australian debut.

Both horses jumped out at Flemington on Friday with the trainer happier with Harlech's performance than Buffalo River's effort.

"I thought Buffalo River travelled OK. It was a firm track and it was an 800 metre jump out where they ran along a bit though," Moroney said.

Although the former English galloper has won five of his six Australian starts, Moroney has two concerns with Buffalo River starting off this campaign.

"He's hasn't beaten much and he's been winning on tracks with a bit of give in them. Also, I think he's a 1600 metre to 2000 metre horse," Moroney said.

Moroney said Buffalo River was being aimed at the Toorak Handicap at Caulfield and the Cantala Stakes at Flemington.

On the positive side heading towards the Sir Rupert Clarke Stakes, he said Buffalo River had won first-up last campaign over 1400 metres and if he got into the field he would be a great light-weight chance.

"There's going to be good speed if he gets in and he's got such a high cruising speed," Moroney said.

"He should be able to tuck in behind the likes of Begood Toya Mother and Streets Of Avalon and then put the pressure on them."

Buffalo River hasn't started since winning at Sandown on May 2

Moroney said Harlech had pleased him in three jump outs with his best one last Friday.

"He's a smart horse. He's finished second to Catalyst and although he was well beaten he should have finished closer," Moroney said.

"He also finished second to Travelling Light at Group One level and she's a top horse."

Harlech hasn't started since he finished fourth in the Karaka Millions behind Probabeel at Ellerslie in January but has subsequently had bone chips removed.

Harlech will be ridden by Michael Dee who was his rider in New Zealand for his last three starts.

Moroney's stayer Chapada will resume in the Naturalism Stakes at Caulfield in the hope of gaining a golden ticket into the Caulfield Cup.