Archipenko to block Mount Nelson ascent but Plan offers Ballydoyle a different route

Chicago began the week with such an operatic tempest that even this proud, virile metropolis seemed to tremble feebly in its path. At Arlington Park, out in the north-western suburbs, 2,500 thoroughbreds cowered in their stalls, pondering what unearthly rage had been unleashed upon the communal barns of the back stretch. But as the storm rumbled away, the skies introduced them to another, rather more tangible menace.

Most of the animals stabled here are mere cogs in the pari-mutuel machine. But now a horse with a genuine role in Turf history had been flown into their midst, opening up a new frontier in what promises to be a season of unprecedented achievement for his trainer. Mount Nelson has already contributed to Aidan O'Brien's haul of 17 Group One prizes this year, winning the Eclipse Stakes at Sandown last month, and his challenge for the Arlington Million represents a new phase in the journey towards Bobby Frankel's world record of 25.

Mount Nelson and Plan, in the Secretariat Stakes for three-year-olds, are O'Brien's first runners outside Europe this year, and as such will serve as pathfinders for the stable's biggest guns in the closing stages of the campaign. O'Brien is already looking formidably equipped for the Breeders' Cup, and it was interesting to see that he has made a couple of dozen entries at the Melbourne Spring Carnival, too.

It might mischievously be wondered whether this sudden interest in Australia has anything to do with the new investments made there in recent months by Sheikh Mohammed, the habitual adversary of O'Brien's patrons at Coolmore Stud. Certainly the Sheikh might feel a frisson of irritation if his horses proved unable to escape the tentacles of Coolmore even in this new, faraway theatre.

Regardless, Mount Nelson looks eligible to lay down a marker for Ballydoyle. O'Brien saddled the last European winner of the Million in Powerscourt, in 2005, the same horse having been disqualified after passing the post first the previous year. And Mount Nelson's record is itself instructive of their trainer's persevering nature.

Last year, judging the stable's Epsom types on the springtime gallops, Kieren Fallon identified Mount Nelson as the one most likely to win the Derby during his suspension. But the colt developed problems and did not surface until running down the field in the Champion Stakes in October. This year, O'Brien started from scratch. And after showing fresh signs of life at Royal Ascot, short of room before staying on well over a mile, Mount Nelson proved suited by a return to this distance at Sandown, always seeming to have matters in hand despite ultimately winning only in a photo.

Significantly, he still seemed green under pressure, suggesting that he might yet make the sort of progress achieved by so many Ballydoyle horses once the foundations have been laid. For O'Brien would certainly identify with Abraham Lincoln, a man forever associated with Illinois, when he observed: "If I had eight hours to chop down a tree, I'd spend six sharpening my axe."

The irony is being lost on nobody, however, that the outstanding danger to Mount Nelson was himself at Ballydoyle last season. Archipenko never built on his success in the Derrinstown Trial, and few trainers would dream of taking on a challenge that appeared to have thwarted O'Brien himself. But Mike de Kock is one of the few to have both the confidence and competence to do so, and has effected a wondrous transformation in Archipenko.

Kevin Shea, his jockey, candidly says that Archipenko was a nervous wreck when he entered the care of the pioneering South African trainer. But the horse has quickly scaled the ladder in blinkers, winning a massive prize in Hong Kong and then returning from a break to win his prep race at Ascot last month.

His proven ability to soak up travel makes him a marginally safer bet than Mount Nelson, but Plan can ensure that the Ballydoyle incursion still pays off. Still lightly raced, he showed improvement when tried over a ninth furlong at the Curragh last month and, against a fairly meek home defence, more can be expected today over a tenth. Plan has a stallion's pedigree, by Storm Cat out of a Breeders' Cup Distaff winner, and his breakthrough at this level can sugar the pill for Coolmore if Archipenko – himself from the family of Nureyev and Sadler's Wells – reproaches them for letting him go.

Ricardo and Baze bring style to Ascot

Racing as a game without frontiers has certainly blossomed since the Arlington Million first began to dismantle them in the 1980s, Tolomeo and Teleprompter twice exporting the prize to Europe in the first five runnings. How fitting, then, that the day's principal entertainment on the home front should be a first encounter between the two most prolific riders in Turf history: Jorge Ricardo of Brazil, and Russell Baze of, well, Bay Meadows.

The only men to have ridden 10,000 winners keep exchanging the overall lead – at present in the hands of Ricardo – but will be riding in the same cause today in the Dubai Duty Free Shergar Cup. This jockeys' team challenge continues to provoke the purists, who treat it with patronising tolerance at best, but Ascot is proving equal to similar disdain on other fronts and nobody should underestimate the historic resonance of this occasion. Both Ricardo and Baze have largely plied heir trade in the sport's backwaters, but their presence today dignifies one of its greatest stages.

The competition also features a British debut for the Turkish champion, Halis Karatas, and a home team that resourcefully combines two role models in Hayley Turner and Frankie Dettori. Certainly all the riders should be fully motivated, with good prizemoney and fields confined to just 10 runners.

Unfortunately the forecast suggests that rain is on its way, and suitabilityto soft ground makes Kaldoun Kingdom (next best 2.20) and Bogside Threatre (2.55) solid bets. Ricardo has sound prospects on Candle (3.30), a winner in the mud who was the only one to get involved from off the pace at Newmarket last time.

US Ranger may at last have his day

After riding Mount Nelson and Plan in Chicago, Johnny Murtagh will jump straight on to a plane to assist in the next chapter of the stable's Group One epic at Deauville tomorrow.

Both US Ranger and Astronomer Royal follow Marchand d'Or – their narrow conqueror on neutral soil in the July Cup at Newmarket – to his backyard in the Prix Maurice de Gheest.

This is very much a home game for the fast finisher Marchand d'Or, who has won the last two runnings of Europe's only top prize over six and a half furlongs. But his obvious prospects will be reflected in the odds, and his quirks make him a precarious proposition for punters.

Pack's vignette lifts Saratoga season

Arlington's marathon summer meeting provides some blue-collar ballast to the light-headed indulgences of Del Mar, on the West Coast, and Saratoga in the East. Chicago has its own, overwhelming magnetism, of course, whereas Del Mar and Saratoga derive all their flavour from the annual migration of the horseracing circus.

Those who want to sample the intoxication of Saratoga are recommended the current edition of the American magazine, The Horseplayer, which features a nostalgic contribution by Harvey Pack, a veteran New York broadcaster and punter – or "handicapper" as they are styled here.

Pack's favourite Saratoga jockey was Angel Cordero, who one day took a fall in the last. "I heard the siren as the ambulance took him away, and choked up on TV," Pack writes. "The next day the bum beat me in the first."

His best vignette dates back to 1974, when the stewards' lift abruptly plunged to the bottom of the shaft, taking with it a hapless operator, Leo. The accident was not discovered until after the race, by the Jockey Club steward, Bud Hyland, who summoned help.

"There was panic," recalls Pack. "The door to the shaft was forced open with a crowbar... Bud shouted, 'Leo! Leo! Are you okay?' There was no answer. Now Bud feared the worst. 'Leo! Do you hear me? It's Bud. Are you hurt?' After a short pause, a little voice was heard from the bottom of the elevator shaft. 'Mr Hyland... Mr Hyland... who won the third?'"