It's hooray for Henry and in-form Ballydoyle on day one of Royal Ascot

Duke Of Marmalade in today's Prince of Wales's Stakes and Yeats in tomorrow's Gold Cup are still champing at the bit as Murtagh, who started yesterday at Evens to lift the crown, ended it 2-7.

Dream team: Johnny Murtagh and Henrythenavigator win the St James¿s Palace Stakes

But whatever that formidable duo do, they will struggle to match the impact of Henrythenavigator.

Murtagh had already bagged his first Group One of the week on the Australian import Haradasun in the Queen Anne when he got the leg up on the dual Guineas winner.

A course record later - the 4-7 favourite completed the mile of the St James's Palace. Stakes in 1min 38.70sec - it was time for the Group One superlatives to flow after Murtagh was able to get his reins in a twist but still brush aside Raven's Pass much easier than the three-quarter length margin suggests, with Twice Over another two-and-a-half lengths away in third.

The victory meant Henrythenavigator emulated Right Tack (1969) and his illustrious stablemate Rock Of Gibraltar (2002) in adding the royal meeting prize to victory in both English and Irish Guineas.

O'Brien, whose star milers in the past have also included Hawk Wing and Giant's Causeway, is often accused of conducting his post-race press conferences with one eye on marketing their future stallion careers for his Coolmore Stud bosses.

But there was far more substance than hype when he put Henry at the top of the pile. He said: 'I find it hard to say we'll ever have a better one than him. He's a great horse. He has speed, stamina, class, he picks up well and he has a great attitude.

'Johnny was telling us all the time after the English Guineas what would happen in the Irish Guineas. He's been riding him in all his work and he was saying what was going to happen today. In the vein of form he is in at present, he's an unbelievable racehorse.'

Where he goes now will be down to the Ballydoyle brains' trust. He could stick at a mile, like The Rock did, or try to prove his versatility at different trips.

O'Brien added: 'You could drop him back, step him up in trip or leave him at a mile.'

If he sticks at a mile, the Breeders' Cup will ultimately be Henry's target. That's the destination for yesterday's runner-up Raven's Pass, whose tenacious effort justified trainer John Gosden's faith in his stamina.

The double took O'Brien's Group One tally to eight this season Godolphin are stuck on one and a season that has yet to take off for them was summed up when their main runner, Rio De La Plata, was ruled out by the fast going.

It took until the fourth race for a British winner when Michael Bell's Art Connoisseur won the Coventry Stakes.

The colt may not have matched the merit of Henrythenavigator, but he earned quotes as short as 12-1 to emulate the O'Brien colt in next year's 2,000 Guineas.