THE Irish-bred Loughan Glen and Clark Montgomery threw down their challenge to Rolex Kentucky defending champion Michael Jung, as the American rider sits top of the dressage leader board after two days of action.

Irish-bred horses have also enjoyed a strong start at North America’s only four-star event, occupying 50% of the top-20 places, including third-placed Cooley Cross Border. And from the 59-strong startlist, Ireland’s two riders - Aidan Keogh (equal 23rd) and Tim Bourke (41st) - produced solid performances before this morning’s cross-country phase when the weather, with temperatures set to soar into the 90s, will prove as much a challenge as the true four-star course.

Keogh was elated after Master Tredstep, having the second four-star run of his career, improved on his 2013 dressage score (57.2) at Pau in 2013 by 8.6 marks yesterday (48.6). “It was just a dream come true,” remarked the Tredstep Ireland entrepreneur, supported by his family, plus Paddy Hughes who owns the Kings Master gelding and trainer William Micklem.

Rueing a couple of tense flying changes, the only blip in an otherwise accurate test, Keogh was keen to tackle Derek di Grazia’s cross-country track, where he felt Fence 4 The Mighty Moguls will ask the first question.

Drawn 12th in the morning’s order, Master Tredstep and Keogh had a tough act to follow when the dressage specialist Loughan Glen and Clark Montgomery overtook the early morning leader Fernhill By Night and compatriot Elisabeth Halliday-Sharp. The Limmerick gelding produced a powerful, uphill test (33.6) for Montgomery, which saw the pair nearly matching their best four-star dressage result (33.3) at Badminton in 2013, when they also led the pack going into the cross-country phase.

Drawn 18th in the dressage order, Tim Bourke was in the middle of a start list which included Cooley Cross Border ((41.0) and Kim Severson; High Kingdom, bred by Micklem, with Britain’s sole representative Zara Tindall (46.6) and the ‘Kentucky King’ Michael Jung on fischerRocana.

Bourke’s cross-country machine Luckaun Quality produced his second-best Rolex dressage score (57.2) from the O.B.O.S Quality 12-year-old’s four appearances here. Westport-born Bourke also led the Irish Horse Gateway course walk in the evening around a thronged Kentucky Horse Park, where the going was good to firm before early Saturday morning heavy showers.

Severson, like Jung, has won the Rolex Kentucky three times with Winsome Adante (2002, 2004, 2005) although the German ace, unbeaten on Lexington turf, is bidding for the first back-to-back treble with his fischerRocana. Cooley Cross Border, Kim’s latest top horse, is making his four-star debut and the Diamond Roller 10-year-old produced a polished test to temporarily take second place.

That was before spectators around the warm-up arena made a beeline for the grandstand to watch reigning Olympic, European and Rolex Kentucky champion Michael Jung. Fourth after dressage (39.3) at her first Rolex appearance in 2015, she led after the first phase last year (34.4) and yesterday’s result (37.1) slotted in between those scores.

“FischerRocana was very nice to ride, very relaxed, so I can try to go forward and push her a little bit to very good marks. I think it was a very good test for her, but maybe not good enough,” said the world number one-ranked rider.

SPECIAL PRESENTATION

Jung received a replica of the Rolex Grand Slam trophy, which he won last year after consecutive Burghley, Rolex and Badminton wins, at a special presentation yesterday. Heading next to Badminton, where he will compete his London and Rio Olympic champion La Biosthetique Sam, he was noncommittal about retirement plans for Sam, saying: “Maybe its his last competition, maybe it’s his last year, maybe it’s its last years. We will see”.

In a year which has seen several top horses retire, including the Irish-bred Flexible and Ballynoecastle RM’s upcoming retirement ceremony tomorrow (Sunday), another to bow out at the top was Arthur. He and Allison Springer (USA) performed the last dressage test of the day as a special concession after the handsome chesnut, by the I’m A Star son Brandenburgs Windstar, was withdrawn from the competition earlier this week. Second after dressage last year to fischerRocana, Arthur will now compete at lower level dressage and show jumping in his retirement.

On past form, Michael Jung is in a strong position with his 2014 World Equestrian Games team gold medallist mare having an excellent Rolex record. She was the fastest horse cross-country last year, picking up just 0.8 time penalties while she was one of just six clears on her 2015 debut.

Loughan Glen has had a more chequered cross-country career, having been eliminated at his only other Rolex start in 2012, then retiring on course at Badminton and the Olympic Games in Rio de Janeiro last summer when the pair were on the US team. After a veterinary issue was since ironed out, the imposing bay has won and placed second in both his three-star starts this spring. Hot on the leading pair’s heels are a pack of cross-country specialists before Sunday’s show jumping ultimately decides this year’s Rolex Kentucky champion.

Follow today’s cross-country live Twitter updates @TheIrishFieldHW where the first horse is due to start cross-country at 3pm Irish time.