Infinity Endeavour’s pedigree says he will get over even more ground in time but a step up to 1,400m should suffice second-up on Sunday at Sha Tin.

The John Size-trained three-year-old is by Fastnet Rock out of New Zealand-bred mare Black Mamba, a Grade One winner at 1,800m and competitive over a mile and a half at top level in the United States.

Black Mamba was raced by Siu Pak Kwan and finished her career with an unplaced run in the 2009 Hong Kong Vase, after which the daughter of Black Minnaloushe was retained as a broodmare.

So, like 2014-15 Griffin of the Year Thewizardofoz, Infinity Endeavour is a home bred, and just like his stablemate, there is no guarantee a studbook page will translate into on-track stamina.

It was thought Thewizardofoz, by Redoute’s Choice and out of a New Zealand Oaks winner, Princess Coup, would get the 2,000m of the Hong Kong Derby in his four-year-old season.

As it turned out, Thewizardofoz didn’t even get a chance to try, flopping in the Hong Kong Classic Mile, but has since returned successfully to sprinting after a number of setbacks.

It isn’t just breeding that indicates Infinity Endeavour will be more effective this time, but the way the three-year-old has finished off at his only two starts, both over 1,200m.

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First-up with blinkers on, Infinity Endeavour basically threw away what looked like being a certain win when his inexperience showed.

After travelling a touch greenly in the run, he loomed to win but hung in and then shied away from the winner Star Of Patch over the closing stages.

Size was set to step Infinity Endeavour up to 1,400m before a blood abnormality sidelined the gelding scratched from what would have been his second start three weeks later.

The ever-patient trainer then sent Infinity Endeavour back to the trials four times for some remedial work.

Upon his return, and not surprisingly, Infinity Endeavour showed marked improvement in racing manners, matching motors with handy looking three-year-old Sight Leader right to the line.

Still, Infinity Endeavour wasn’t perfect; when placed into the starting barriers he leant back on the stalls and had to be reloaded.

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After a successful stalls test, Size has picked out the Celosia Handicap and the Class Four doesn’t look overly strong.

Relentless Me (Zac Purton) seems the obvious danger on paper after a closing effort on debut but his chances were dealt a blow when he drew wide.

Karis Teetan has to find a way in from barrier eight on Infinity Endeavour, but provided the horse’s barrier quirks have been ironed out, he should have options at the start.

Joao Moreira has his usual strong book of mounts and has benefited from Brett Prebble’s absence by picking up the ride on Jumbo Luck in the Class Four Balsamine Handicap (1,200m).

Jumbo Luck failed as a short-priced favourite last start, seeming to feel the ground on a quick back up.

Trainer Francis Lui Kin-wai has given the gelding a better break between runs this time and two encouraging trials have Jumbo Luck primed for a return.

The challenge for Moreira will be where to slot the four-year-old in the run from barrier 12 with the rail out in the C + 3 position.

A comfortable spot in the run won’t be as difficult to find for Moreira on sprinter Regency Bo Bo after the Tony Cruz-trained three-year-old came up with gate two in the Class Three 18 Districts Cup (1,200m).

Regency Bo Bo, a two-time winner this season, has finished second at five of his past six starts and drawn a number of awkward gates during that stretch.

Meanwhile, the Jockey Club has confirmed South ­African rider Callan Murray has been granted a license until the end of the season.