If their impressive last start performances are any indication, rising stars Harmony Hero and Aerohappiness could be bound to clash in the 2019 four-year-old series, but on Saturday both youngsters should continue their progression with wins at Sha Tin.

Other than being three-year-olds with obvious upside, Harmony Hero and Aerohappiness have two very different profiles.

Harmony Hero already had a reputation built on exciting performances in Australia when he arrived with Richard Gibson and has added to the hype with two big runs so far.

Aerohappiness is the prototypical John Size-trained Private Purchase Griffin; there is nothing flashy about his breeding, but he is an untapped talent who won his first race with obvious ratings points in hand.

Both head to the races drawn barrier 11 but with the ability to overcome their draws and opposition.

The nature of both horses’ last start wins – tough efforts when things didn’t go their way – resulted in relatively narrow winning margins and protected both horses at the handicaps.

Harmony Hero should have won first-up, but was stuck wide, and last start at 1,400m found himself giving away a long break to the leader heading into the straight.

Harmony Hero was spotting Sun Touch eight-and-a-half lengths with 400m to go, and still a solid break with 200m to go, but gathered the runaway leader up with a blistering final sectional of 22.39 seconds.

‘I can’t name a better horse, physically, in Hong Kong’: Richard Gibson lauds Harmony Hero

After the win trainer Richard Gibson called Harmony Hero one of the best looking horses in Hong Kong but both he and the winning jockey also indicated that the import still wasn’t 100 per cent fit.

That lack of fitness meant Nash Rawiller didn’t push forward from his gate, wisely so as it turned out, but now the Australian jockey faces a similar situation from the same gate in the Class Two Sports For All Handicap (1,400m).

Harmony Hero has the benefit of another run, which may encourage Rawiller to be bolder tactically, but the race also contains a host of on-pace runners – even if it lacks an obvious leader.

For Aerohappiness, the way the youngster has been stepping away at the start, in trials and then first-up, may mean Joao Moreira has little choice but to be conservative in the Class Four Nurturing Talent Handicap (1,200m).

Last start, Moreira was intent on going forward from gate six but after a slow jump he ended up posted three-wide with no cover on the speed.

“Then he got to the front a little bit too early and wanted to look around, so I had to keep riding him all the way through the line to keep him focused,” Moreira said after the win. “There were a few things against him but he still won and that tells you he has ability. He’s a very intelligent, well-educated horse and feels like later on he might be more of a miler.”

Despite that obvious inclination for longer distances in future, Size has stuck with 1,200m for now, and how Aerohappiness jumps may determine whether Moreira makes a play to go forward.

Ping Hai Star set to target QE II as John Size unveils another smart youngster in Aerohappiness

If Aerohappiness can step cleanly and muster speed, Moreira may be tempted to press forward in a race that contains an obvious leader, Multimax, but not much else in the way of speed.

Two back-markers that could cause the likely favourite trouble are Liverbird Star (Derek Leung Ka-chun) and Complacency (Tommy Berry).

Both horses were beaten by wide margins by Refined Treasure over 1,000m last month but the way they were finding the line indicated a step up in trip would bring about better performances.