Trainer John Size's duo key to Triple Trio success on Sunday

Two horses from the John Size yard can form the basis of Triple Trio selections at Sha Tin on Sunday.

One is an unbeaten and progressive performer who has yet to put a hoof wrong and another a promising middle-distance type who must have had the master trainer pulling his hair out with frustration as he failed to fulfill his potential.

Sea Dragon would be the teacher's pet of the leading stable, while All Bountiful took the dunce cap off last start with a barnstorming, breakthrough performance at Happy Valley, but they are the standout bankers in the final two legs and are both blessed with good barriers.

Sea Dragon has been flawless, winning three from three - all with Douglas Whyte aboard, who rides again this time. The four-year-old drew well on debut, jumping from near the grandstand rail up the straight course, but in two starts since over 1,200m he has drawn double figures.

He has overcome gates 11 and 12, although the first time it took an almighty fight with Bullish Friend when he prevailed by a nose.

Sea Dragon again had to show some toughness. Whyte surged forward from the draw, but Zac Purton kicked up underneath him on Affluence Of Rain and, with the rail out in the "C" configuration kept him three wide on the circle. As it turned out, the win did not look pretty, but Sea Dragon got the job done and gate two this time offsets the typically sharp rise in the ratings.

He has jumped 28 points to 80 in three starts, 10 for the last-start victory, and will carry equal top weight against what looks a very weak Class Three field.

Others to include are The Prince (Vincent Ho Chak-yiu) and dirt-freak Hearts Keeper (Ben So Tik-hung), but it gets very thin from there - Atacx (Tim Clark) and Winnie's Horse (Gerald Mosse) have been in the market at times, but hardly have justified it.

Size had tried everything with All Bountiful (Ben So Tik-hung) changing gear, distances, tracks, tactics and riders, but it took a solid tempo up front for him to find his rhythm and he won going away last start at Happy Valley over 2,200m.

Forget the previous 13 runs, the penny dropped for All Bountiful last time out and the four-year-old has virtually started afresh, still with a relatively low rating of 56.

There might not be the pace he would like this time, but don't be surprised if So finds the front from gate four and ends up close to the speed, likely to be set by Real General (Alvin Ng Ka-chun).

This is a decent Class Four field, Whyte jumps on Holy Mac, who is a chance, even though he has drawn wide, and the blinkers go on Highest Acclaim (Brett Prebble). He looks like a progressive type who will appreciate the space back at Sha Tin.

Others to watch are Malayan Pearl (Tye Angland) and Global Fame (Matthew Chadwick).

In the opening leg, bank on Really The Best (Chadwick) achieving the rare feat of three straight wins in Class Five.

Consider Euphemism (Whyte), last-start winner Backstreet Fighter (Purton), Chantilly (Richard Fourie) and P anther Run (Howard Cheng Yue-tin).

Read Michael Cox's blog – Dirt tracks, dark racecourses and dilated pupils. Go to: http://www.scmp.com/author/michael-cox-0

Track Stars

RACE 1:
(2) Sunny Pearl, (4) Brave Brothers, (6) Multivictory, (10) Star Of Wai Bo.

RACE 2:
(3) Dragimova, (5) Hypersonic, (7) Multiexpress, (10) Bernand's Choice.

RACE 3:
(3) Keen Tactics, (4) Good Friends Magic, (7) Perfect Hedge, (14) Dragon Pins.

RACE 4:
(2) Bamboo Dance, (3) Humongus, (6) Casa Junior, (11) Sunseeker.

RACE 5:
(1) Choice Treasure, (2) Sea Dragon, (6) Winnie's Horse, (7) Atacx.

RACE 6:
(1) Holy Mac, (3) Highest Acclaim, (5) Malayan Pearl, (6) Panther Run.

RACE 7:
(2) Trump, (4) Little Men, (5) Why Not, (11) Let's Goal.

RACE 8:
(1) Leading City, (2) Arrived Ahead, (3) Supreme Win, (5) Rich Tapestry.

RACE 9:
(2) Pure Champion, (4) Zaidan, (11) Willie Cazals, (12) Taknam.

RACE 10:
(3) Nice Folks, (4) Pretty One, (5) Sea Diamond, (6) Tour De Force.