In typical John Size fashion, the champion trainer was not committing to any particular path post-race but the Group Three Queen Mother Memorial Cup must surely be beckoning for Prawn Baba after he upstaged the Derby horses on Sunday.

Faced with the Derby third and fourth, Exultant (Brett Prebble) and Ruthven (Tommy Berry) and some handy lightweights, Prawn Baba was sent out a double figure chance for the Kowloon Cricket Club Centenary Cup (2,200m) but saw them off to claim just his third victory.

The gelding kept up a strike rate for Olivier Doleuze on Size-trained runners of around 20 per cent this season, after the French rider planted Prawn Baba in the box seat and then trusted the trainer’s instructions.

“When I trialled Prawn Baba the other day it was the first time I had ridden him,” Doleuze explained. “He felt good, with nice gate speed for a staying horse, but the main thing is he is really a rhythm horse. He doesn’t do things fast but he doesn’t stop. Even coming out from behind the leader, John told me the take him to full power because he doesn’t sprint.”

Stablemate Sergeant Titanium was the leader, ensuring an even rather than fast or especially slow tempo, and Doleuze peeled around his heels straightening up to make his run a long way out.

“Actually, when I came around Sergeant Titanium on the last part of the turn, I didn’t feel like I was going that well but I went, he got his momentum up and he was not going to stop,” Doleuze said. “When the others came to challenge him, he fought so hard to the line. I don’t know what John has in mind for him but there are some longer races coming up that would suit him.”

Prawn Baba set to sizzle and upstage Hong Kong Derby contestants at Sha Tin

Size said that the trick for Prawn Baba might have been the rain on race morning which took the edge off the track.

“If you look at his wins this season, he’s had one on the dirt and one today on a track that had some rain on it,” he said. “Inferior going might be the common factor there. On the firm ground, he still runs well but the dirt and today’s surface are just a little bit kinder underfoot and that just might be the difference between him running a good race in defeat and actually winning. Olivier rode him the way I wanted him ridden – he had a very fit horse and I wanted that fitness to count.”

Size said he had not thought beyond Sunday’s race for a target and would look at the programme, but what he will see there are few opportunities for a stayer rated in triple figures if he does bypass the Queen Mother Memorial Cup (2,400m) on May 6.

Trainer Tony Cruz said he had not been disappointed with Exultant’s defeat after the gelding had come from near last to run the winner to a length and a quarter.

Exultant and Ruthven set to test Hong Kong Derby form at Sha Tin

“He had a big weight and had a lot of ground to make up,” he said. “Provided he pulls up OK from this race, he’ll go on to the QE II Cup next.”

The John Moore-trained Ruthven had finished alongside Exultant in the Derby but was the major disappointment, running ninth of 10 runners after sitting close in running.

“He’s pulled up with blood in the trachea,” Moore said. “So he’s had an excuse today and he’ll go on to the QE II Cup as planned.”