COURSE DOCTOR can cause a major upset by winning this afternoon's £40,000 Great Yorkshire Chase at Doncaster.

Unless there's a substantial last -minute plunge on the nine-year-old, Course Doctor (3.10) is bound to start at an inviting each-way price of 25-1 or better for the Town Moor showpiece.

And the bookies will certainly be praying for a shock result having taken boatloads of cash for the newly-installed favourite King On The Run, backed down this week from 10-1 to 4-1.

Course Doctor's credentials are not immediately obvious, but in such cases it sometimes pays to dig just that little bit deeper. And for the record, a couple of seasons ago he looked like a novice chaser bound for the very top following a hat-trick of authoritative victories at Ayr.

Trained at the time by Middleham handler George Moore, Course Doctor (3.10) was subsequently plagued by jumping problems, so much so that Moore eventually resorted to putting the gelding back over hurdles.

And it was a ploy which paid handsome dividends when the distinctive chestnut galloped a decent field of staying hurdlers into a state of groggy submission over three miles at Aintree in October.

Not long after the victory Course Doctor changed hands for a hefty 40,000 guineas and is now in the care of Burnhope-based rookie trainer Alan Dickman.

Many moons ago Alan partnered some of Peter Easterby's best inmates and it comes as no surprise to see him make such a promising start to his training career.

He sensibly gave Course Doctor a confidence-boosting spin around Wetherby this month, a pipe-opener which will have put him spot-on for today's ultra-tough assignment.

In the earlier Letherby & Christopher Handicap Hurdle, Happy Change (1.45), a rare runner over jumps for Mark Johnston, embarks on an ambitious plan leading up to a crack at the forthcoming Champion Hurdle.

Not many individuals with the heady Flat rating possessed by Happy Change are switched to the National Hunt arena, and he will surely have the speed to outgun the opposition up the home straight, provided the nine flights of hurdles don't get in his way!

When recently asked by a Racing Channel reporter for a horse-to-follow in the near future, Mary Reveley unhesitatingly replied "Loop The Loup", running for only the second time over timber in the two-and-a-half-mile Dalby Handicap Hurdle.

Loop The Loup (2.05) is taking on some far more experienced rivals than himself, but on the plus side was immensely impressive on his Musselburgh debut, consequently Mrs Reveley's faith could well be justified in the £7,200 event

Cheltenham stage an equally high-quality fixture, although the shameful turn-out of only four runners for the £75,000 Pillar Property Chase beggars belief in an era when owners and trainers alike are constantly bemoaning the low levels of prize money on offer.

Of the quartet, the most interesting contender is without question the returning Cyfor Malta (2.50), not seen out since winning this race two years ago.

On that occasion he accounted for See More Business, who within the space of ten weeks went on to lift the Gold Cup. The latter re-opposes again but despite having a potential fitness advantage, could struggle to reverse the form against Cyfor Malta, regarded by his jockey Tony McCoy as one of the best he has ever ridden.

There's plenty of northern interest on the card, including Richard Fahey's pair Dhaudeloup (1.45) and The Butterwick Kid (2.20).

Having unsuccessfully employed hold-up tactics on Dhaudeloup, Fahey changed tack and it worked a treat when the six-year-old made all to score at Doncaster in December.

The Butterwick Kid will be operating over a trip slightly short of his best in the two-mile-and-five-furlong in the Timeform Novices' Handicap. Nevertheless the presence of Prestbury Park's daunting uphill finish should be sufficient to bring The Butterwick Kid's superior stamina into full play.

The Cleeve Hurdle features last year's empahtic winner, Lady Rebecca, as well as Tim Easterby's Barton (3.30), a Festival scorer two years previous in the SunAlliance Novices' Hurdle.

Lady Rebecca is a fantastic mare but I still favour Barton, one of the most imposing thoroughbred's currently in training.

Len Lungo's Beaver Run (1.05) should extend her winning sequence to five in the opening EBF Novices' Hurdle at Ayr.

Beaver Run's rate of improvement this term has been quite startling, especially as she only showed a modicum of promise last season.

Don't take any notice of her latest three-length winning margin at Haydock - Tony Dobbin could have won by four times the distance had he not eased his mount right down to a virtual walk over the final 50 yards.

Track specialist Solsgirth (1.35) ran as if his legs were tied together at Newcastle 37 days ago. Forget that dismal display and he's the one to be on in the weakly-contested Burns Cottage Handicap Chase