Casey won his first European Tour title north of the border in 2001 when he claimed the Diageo Championship at Gleneagles while Thomas Levet produced the most emotional of his three European Tour victories last week in The Barclays Scottish Open at Loch Lomond, a victory which gave him his place at Royal Troon.
And the two were back at their best in the west of Scotland again, closely followed by New Zealand’s Michael Campbell, who finished runner-up to Levet at Loch Lomond, and proved he was still bang in form with an opening four under par 67.
Casey, who celebrates his 27th birthday next week, continued in the same vein of form which has seen him post seven top 15 finishes this season on The European Tour. One of those came at Augusta National where he finished tied for sixth in the Masters Tournament and the Englishman again proved he was at home in a Major arena.
“I played well at Augusta and in The Players Championship earlier this year and I do feel that my game has progressed to this level. This is what we prepare for and practice for, to play in big tournaments like this, so there is no reason why I shouldn’t be relaxed.”
Three birdies in the front nine helped Casey to the turn in 34 and the three time winner on The European Tour International Schedule was quickly back on the hunt for birdies turning for home, picking up a shot at the tenth and another at the treacherous 11th where he rolled in a 40 foot putt for birdie.
A shot went at the 12th but the Englishman shrugged off the error in superb style, rolling in a 30 footer for birdie on the 16th and another from 18 feet at the 18th to outshine his playing partners, which included Masters Tournament Champion Phil Mickelson, who carded a 73.
He bogeyed the tenth but recovered superbly with a birdie at the 11th and parred every hole on the way in, apart from the 17th, where he rolled in a 25 foot putt for birdie to ensure him a share of the lead.
"I feel my game is exactly the same as it was at Loch Lomond," said Levet. "I felt I was in control on the course and I tried to stay calm . It helps that I like this type of golf too, you don't have to be too long but you have to be straight and you have to concentrate on every shot to find the fairways and greens, because you don't want to be in the bunkers, they are no fun!"
Closest challenger to the leading pair was Campbell, continuing the excellent opening day for The European Tour contingent and giving hope that the run of American winners in the last five Open Golf Championships at Royal Troon, might be about to be broken.
One shot behind Campbell, there was further good news for The European Tour contingent from Gary Evans, Kenneth Ferrie, Mårten Olander and Vijay Singh who featured in a group of players who opened with a 68, amongst who was also Amateur Champion Stuart Wilson of Scotland who produced a tremendous first round.
Evans, out in the first group of the day at 6.30am, posted the early clubhouse mark after being assisted by the remarkable events at the fourth hole, propelling his ball into the hole with a five iron from all of 227 yards, for the fourth albatross of The 2004 European Tour season.
“My partners both took three wood from the tee but I took driver to get past the bunkers,” said Evans. “I then hit a pretty decent five iron which was bounding nicely up to the green, I turned to put my club back in my bag and then heard an almighty cheer from the greenside and looked up and everybody had their arms in the air.
Later in the day Evans was joined by his fellow Englishman Kenneth Ferrie, who got to the three under par mark thanks to a superb approach shot to the last which left him a mere four foot putt for birdie, while Sweden's Olander and Fiji's Singh both parred the last for their 68s.
Other European Tour Members to get under 70 on the opening day were Darren Clarke, Ernie Els, Joakim Haeggman, Trevor Immelman, Retief Goosen, Barry Lane, Paul McGinley and Colin Montgomerie, who all opened with 69. Of the group, Els and Clarke were the most frustrated, Els taking two in a bunker for a double bogey five at the 17th while Clarke fired his five iron approach to the last over the green and out of bounds on his way to a double bogey six.
It was the end of a roller-coaster day for Els especially, who had propelled himself up the leaderboard on the outward half after holing in one with his wedge at the 128 yard Postage Stamp eighth hole.
Montgomerie did well, recovering from shedding three shots in two holes at the tenth and 11th to birdie the 12th and 15th to get back into red figures.
And McGinley once again preserved the integrity of the game of golf by calling a penalty shot on himself on the first green when his ball moved at address. The Irishman bogeyed the hole, but more than made up for that with three birdies elsewhere, including one each at the second and third.