Golf is a numbers game and if Padraig Harrington is to avoid finishing second best in the Order of Merit for the third time in his career he will need to produce some impressive figures of his own at Valderrama today.

Three successive back nine bogeys in a third round 72 saw the Dubliner slither back into a share of 13th place in an event he must win to avoid the need for furious use of the pocket calculator this afternoon.

Yes, second place may well be good enough for him to finish ahead of the current Order of Merit leader Paul Casey and claim the Vardon Trophy for the first time in his career.

But if England’s David Howell or Sweden’s Robert Karlsson happen to lift the Volvo Masters title ahead of him, a potential 30th second place finish may leave Harrington feeling as sick as vividly colored bird with a short down-curved hooked bill and grasping feet.

Winning on demand is something that appears to be within the compass Tiger Woods and while Harrington is still clinging to the hope that he can somehow rescue this one from the bonfire, he all but admitted yesterday that he may need the putting round of his life to pull off a remarkable double-whammy.

Starting the day in a share of ninth place, four strokes off the lead, he did the hard bit by playing the front nine in two under par 33 to move to second place on the leaderboard, but then contrived to undo all his good work in the space of 20 minutes.

This time it wasn’t wayward driving or errant iron-play that caused his downfall, but a poor chip and a series of even poorer putts that led to three successive bogeys from the 14th hole.

Failing to chip and putt from 40 feet at the 14th was excusable, but three putts at the 15th, and again the 16th where he had an eight footer for a momentum restoring birdie, turned what promised to be a day to remember into another frustrating one.

Harrington’s problem now is that not only is he four strokes adrift of surprise leader Jeev Milkha Singh of India, but that his two biggest rivals for the Order of Merit crown are one stroke ahead of him on a star-studded leaderboard.

Singh, this year’s Volvo China Open winner, hit a three under par 68 to lead by a stroke on three under par from the talented quartet of Henrik Stenson, Johan Edfors, Lee Westwood and local hero Sergio Garcia with Howell and Karlsson in a star-studded five-man group on level par.

Providing Karlsson and Howell fail to win, Harrington could afford to finish alone in third and still win the Order of Merit, but only if Casey finishes outside the top 35.

That seems unlikely as Casey is fit again after his tummy troubles and already up to 32nd after carding a level par 71 on the windswept Sotogrande track yesterday.

“Four shots behind going out tomorrow wouldn’t be the end of the world, only there’s a lot of people between me and the lead,” Harrington said. “You’ve got to think somebody in there is going to shoot a decent score so you’ve got to think of four, five or six under for a winning score. If that’s the case, I’ve got a lot of work to do.”

Harrington certainly won’t be playing for second place, though the 30th runner-up finish of his career might well be enough to make him European No 1 for the first time.

His brilliant short game kept him in the game for nine holes yesterday before it all went pear-shaped on the back nine, complicating his bid to become just the second Irishman to win the Order of Merit.

The world number 11 got off to a fast start when the played the first four holes in two under par, saved great pars at the seventh and eighth and then resolved another delicate situation at the ninth, where he was blocked out by trees on the left but drilled a five-iron under the branches to 40 feet and two putted.

A sloppy bogey at the 10th, where lipped out from five feet after chunking his short iron approach to a tricky front pin, was erased with a birdie at the 11th.

But that a series of damaging ‘blips’ at the next three holes have severely damaged his chances.

“I can’t keep putting myself in these positions,” Harrington said. “It was tough after the first round and it is a long way back now from where I am.

“I have a difficult day ahead of me tomorrow but if I play the same way that I played today I will need a very good day on the greens.

“I think I struggled a bit with pace on the greens. I'm just not getting my pace right. I'm leaving myself some awkward putts back and if you keep doing that you're going to miss some and when you start missing them you lose a bit of confidence.

“I've got to go out there and win it so I've been focussing my trying to do my best this week to get myself up near the top and be in contention with nine to go, if you're in contention with nine holes to go anything can happen.”