Steven Arnold knew he had ridden a potential star when he won last year's Listed Anzac Day Stakes at Flemington.

Arnold steered the Darley galloper Long John to an easy win to confirm his opinion he was riding an exciting two-year-old.

"He carried 59 (kilograms) and he killed them and after that win, you could tell he was a very good horse," Arnold said.

Long John went on to win the Group One Caulfield Guineas as a spring three-year-old before heading to Dubai to join owner Sheikh Mohammed bin Rashid Al Maktoum's Godolphin outfit.

Arnold will ride the Mike Moroney-trained Merion in Friday's Anzac Day Stakes as he shoots for his third consecutive win in the race.

Long John and Merion began their careers in similar fashion, winning Bendigo maiden races.

However Long John struggled in his jump-outs at Flemington before blinkers were applied but Arnold said Merion had performed professionally from the day he entered Moroney's stable.

"He's a nice progressive horse with a good attitude," Arnold said.

"I gave him two jump-outs and I was quite taken by him."

Merion's bid to remain unbeaten in the Anzac Day Stakes was made slightly easier by the withdrawal of the Mick Price-trained Pressing.

Pressing won impressively on debut at Caulfield but a wide draw caused Price to scratch the Sebring colt.

"There's a $120,000 Listed race at Caulfield next week so I scratched him from Flemington and he's going there," Price said.

Price's fellow Caulfield trainer Peter Moody could reduce the Anzac Day Stakes numbers further by withdrawing his three runners.

Moody's trio Easy Drama, Sweet And Speedy and Armada have drawn barriers 15, 17 and 20 respectively which Moody said meant the youngsters were all likely to miss the race.