DESERT KING silenced the doubters in yesterday's Budweiser Irish Derby at the Curragh and, with his thrilling victory, provided further evidence that his trainer, Aidan O'Brien, possesses a rare talent.

As the Christy Roche-ridden colt accelerated past the gallant outsider, Dr Johnson, in the final furlong to win by a length, it was the final confirmation of the passing of that mantle from the old maestro Vincent O'Brien to his young namesake.

Six times the older man won the Derby as a trainer, and for a few strides yesterday it looked like being a fairytale result when Dr Johnson, trained for him by his son Charles, went into the lead. Time could have stopped for all the nostalgia such a result would have produced, but when Desert King struggled past, it only proved that time moves on. Now is Aidan O'Brien's time.

Desert King proved that. The Irish 2,000 Guineas winner had been dismissed as a likely non-stayer in the Derby after flopping in Royal Ascot's St James's Palace Stakes, but, on O'Brien's insistence, ran yesterday. Instinct proved more accurate than pedigree when Desert King showed the sort of guts that only champions possess to give his trainer a clean sweep in the three classics run so far this season.

The French challenger, Loup Sauvage, ran on strongly to just miss out on second, with the second of O'Brien's three runners, Johan Cruyff, back in fourth. The favourite and Epsom runner-up, Silver Patriarch, faded into fifth in the straight and was found afterwards to be lame.

Typically. the self-effacing O'Brien tried to present himself as a vessel for a lot of other people's efforts at the famous old Ballydoyle stables, but now the fascinating possibility of a historic clean sweep of the five classics looms. Paddy Prendergast took four of the five in 1963.

O'Brien and joint owners John Magnier and Michael Tabor were content yesterday just to savour the moment, and Tabor who saw his talking horse Entrepreneur fail in the Epsom Derby, said: "Aidan made the decision to run Desert King. He was adamant that if he got the mile and a half he would win. We were deflated after Epsom but now it doesn't get better than this."

Christy Roche's decision to partner Desert King was vindicated in the best way and the 47-year-old gained his third Derby success in 21 attempts. "I wasn't brave enough to desert a Guineas winner," Roche joked, but his judgment that Dr Johnson was the horse to follow in the race was correct.

"If I hadn't ridden Desert King I would have ridden Dr Johnson. He was the one I was worried about. People don't realise the decision I had. From five furlongs out I was happy that I was following the right one. I have no doubt that Desert King is better than my previous winners, Assert and St Jovite," Roche, who didn't rule out retiring at the end of this season, added.

John Murtagh had a first Irish classic snapped from his grasp in heartbreaking fashion and said: "At the two furlong pole, I said to myself `go now' and Dr Johnson quickened really well. Christy just had too much speed."

Olivier Peslier had a slow start on Voup Sauvage but made his ground up well and just failed to snatch second. "The winner was just too strong, hut it rode like a good race with a good pace."

Silver Patriarch was a big disappointment after disputing the lead into the straight and Pat Eddery said: "He just didn't pick up." Trainer John Dunlop was disappointed with the effort but added: "We found a considerable amount of mucus in his respiratory tract and he is also slightly lame.

It was O'Brien's day, however. and the scary thought for his rivals is that he feels that he can only get better. "Desert King is a real champion but we let him down at Ascot by being too soft on him in his preparation for that. We'll know a lot more next year and we'll learn from our mistakes," O'Brien said.

The old maestro would approve.

£1,274,384 was bet with the bookmakers at the Curragh yesterday, an 11 per cent increase on last year's figure. A record £588,977 was bet with the Tote, including £24,000 from France. The previous best was last year's Galway total of £579,959. The Curragh manager, Brian Kavanagh, estimated yesterday's crowd as approaching 31,000.