Size matters, especially if you’re tackling the marathon extended three-and-a-quarter miles of the Cheltenham Gold Cup (3.30pm), steeplechasing’s most prestigious and sought after prize.

Equine greats have decorated their careers with victories in this most demanding of races, chief among them Arkle, Desert Orchid, Best Mate and Kauto Star.

The name to add to the list in 2017?

The bookies would have you believe that the two Dorset stablemates, the Colin Tizzard pair Cue Card and Native River, are the ones to beat, though dangers abound, and not simply from rival horses…

For the magnificent Cue Card, unlucky to be denied by an untimely capsize in this race a year ago, the sands of time could be just as big a factor: 11-years-young, the old man of the group tries to defy a powerful trend, one which tells us that since the year 2000, horses aged 10+ are 0/65 in this race.

Four years his junior, perhaps this race comes a year too soon for the swashbuckling Native River.

Elsewhere among the Gold Cup field, the week could barely be going better for ace trainer Gordon Elliott and his team, as he prepares to unleash Lexus Chase winner Outlander.

Meanwhile, Elliott’s great rival, Willie Mullins, endured a troubling first couple of days, but has high hopes for the French-bred Djakadam, twice placed in this previously.

However, my gut instinct is that the extra yardage will bring out even further improvement in the Jessica Harrington star, Sizing John, the Leopardstown Gold Cup hero who brings untapped potential at staying distances.

Fed up with following Douvan home at a respectful distance over two miles (the score stands at 0-7), he scored readily at Thurles when trying two and a half miles for the first time, and then left that effort behind when seeing off a quality field in Grade 1 company last time out.

His stamina-laden pedigree, alongside the prowess of his in-form yard who struck with Supasundae here on Wednesday, allied to his measured and precise method of jumping tricky fences, all point the way to Sizing John.

I think he’ll win, but take out some insurance and back him each way in a wide open race.

Also to look out for on Gold Cup day, anyone looking to aim a spare fiver each way at something likely to go off at huge odds would do far worse than back Wait For Me in the County Hurdle at 2.10pm.

It makes sense to look towards the foot of the handicap, in a race where all 116 horses rated 140 or more who have lined up since 2005 have come a cropper.

Wait For Me has outstanding Festival form, a feather weight, hails from a stable operating at a 25% strike rate over the past fortnight, and to put the cherry on the icing on the cake will be partnered by the champion jockey, Richard Johnson!

Sent off the 7/1 joint market leader for this race a year ago when fourth, Wait For Me also finished third in the previous year’s Champion Bumper.

He’s lightly-raced, as fit as can be, still only seven, fitted with a first time tongue tie on drying ground, and might yet come good having slid to a very attractive mark.

Finally, perhaps even tougher than the County is the penultimate race of the meeting, the Martin Pipe Conditonal Jockeys’ Handicap Hurdle (4.50pm), in which another who could come good at a big price is Coo Star Sivola.

Coming into this with the highest Racing Post rating of any runner in the 24-strong field, Coo Star Sivola loves it at Cheltenham, posting form figures at the track of 2,3,1,6, including a quality third in last year’s Fred Winter.

Furthermore, his trainer, Nick Williams, thumped in a jubilantly celebrated winner here on Wednesday with 33/1 Flying Tiger getting the upperhand in the Fred Winter.

Despite his long odds, it’s far from impossible that Coo Star Sivola could give him a famous double – back him each way.

Good luck!