What a difference a year makes. Twelve months on from starting the Open championship with a horror round of 85 which he admitted left him "embarrassed and looking stupid" England's Paul Casey posted a 66 today to set the pace at Royal Troon.

The 26-year-old from Surrey, who 11 years ago was one of the youngsters working on the leaderboards at the event, outscored playing partner and current Masters champion Phil Mickelson by an impressive seven strokes.

It was also three better than favourite Ernie Els, who holed-in-one at the "Postage Stamp" eighth but double-bogeyed the 17th, and four better than Tiger Woods.

According to Mickelson, Casey could have been even further ahead of him.

"That was an easy five under," said the American, "and the way he played I wouldn't be surprised one bit if he is on top on Sunday."

Casey, joined by Thomas Levet just four days after the Frenchman's Scottish Open victory gave him a place at Troon, was thrilled at erasing the memory of that nightmare opening at Sandwich last year.

"It's a sign I'm more relaxed and not getting in my own way now. Major championships are a big deal, but you have to treat them as every other event. If you don't then 85s happen.

"If you try too hard you don't succeed. You just have to try the right amount. You've got to want it a lot, but not push it over the edge and find a happy medium.

"We found it a week in April and hopefully we'll find it for a whole week here."

That was a reference to his sixth place on his debut in the Masters at Augusta, by far the best performance of his career in the majors so far. He has played only six others - and missed the cut in five of them.

Casey is aiming big, though. He openly admits his target is to join the elite group of Gene Sarazen, Ben Hogan, Jack Nicklaus, Gary Player and Tiger Woods who have won career Grand Slams.

That, he believes, set him apart from some of his colleagues on the European tour.

On Tuesday Casey accused them of showing "the George Best syndrome" and, despite some backlash, he was not backing down from his comments when questioned again.

"Maybe a few guys are too content being journeymen," he stated. "I want to play on the world stage, play against the best.

"Why would you want to be content with just playing on the European tour?

"There are definitely a few who have potential and don't want to capitalise on it."

Casey, who won all his four games in the Walker Cup victory over America at Nairn in 1999, turned professional after finishing second in the world amateur team championship and was a college star at Arizona State.

That was where he first met Mickelson and since he has kept a home in Scottsdale they have played many rounds together.

"I've only beaten him once or twice. I still have a lot of catching up to do, but when I was paired with him I thought it was fantastic. And Shigeki (Maruyama) is a lot of fun too.

"The goal tomorrow is try to outsmile him."

As well, of course, as repeat a round in which he made up for bogeys on the ninth and 12th with birdies at the first, fourth, eighth, 10th, 11th, 16th and 18th. The final two came with putts of 30 and 16 feet.

A smile has not left Levet's face since he shot his closing 63 at Loch Lomond and suddenly had to change plans for a week off.

The 35-year-old, beaten by Ernie Els at Muirfield two years ago only at the fifth hole of a play-off, had four birdies in five holes from the fourth and had the added bonus of a 33-foot putt on the 222-yard 17th.

"I just hope my game stays the same and my mind stays the same," he said. "When you play that well you don't really feel the pressure because you know you're going to make things happen.

"I must have heard 'well done at Loch Lomond' about 50,000 times this week already. It's nice."

Maybe it will be third time lucky for the French following his own near miss and Jean Van de Velde's self-destruction at Carnoustie in 1999 from three ahead with one to play.

Casey and Levet led by a stroke from New Zealander Michael Campbell - second last weekend and third in the 1995 Open - and Scot Alastair Forsyth, who was in the penultimate group of the day and still had nine to play.

The bunch two behind included British amateur champion Stuart Wilson, from Forfar, England's Kenneth Ferrie and Gary Evans and world number three Vijay Singh.

Evans, who teed off in the opening group at 6.30am, could even claim the shot of the day ahead of Els since he sank a 226-yard five-iron for an albatross two on the fourth.

Darren Clarke, runner-up at Troon in 1997, and Colin Montgomerie, playing on his home course, both shot 69 - Clarke double-bogeyed the last after sending his five-iron approach over the green and out of bounds at the last - but Padraig Harrington could manage only a 76 and Sergio Garcia did only one better.

Forsyth, 43rd on this season's European Tour Order of Merit, bogeyed the 12th, but came back with birdies at the 13th and 15th to join Casey and Levet out in front.

Collated first-round scores (Gbr & Irl unless stated, (x) denotes amateur, Par 71)

66 Paul Casey, Thomas Levet (Fra)

67 Michael Campbell (Nzl)

68 Gary Evans, K.J. Choi (Kor), Carl Pettersson (Swe), Matthew Goggin (Aus), Kenneth Ferrie, (x) Stuart Wilson, Vijay Singh (Fij), Marten Olander (Swe)

69 Barry Lane, Rich Beem (USA), Paul McGinley, Ernie Els (Rsa), Skip Kendall (USA), Colin Montgomerie, Scott Verplank (USA), Trevor Immelman (Rsa), Joakim Haeggman (Swe), Darren Clarke, Kenny Perry (USA), Retief Goosen (Rsa), Steve Lowery (USA)

70 Sandy Lyle, Shaun Micheel (USA), Justin Leonard (USA), Mathias Gronberg (Swe), Takashi Kamiyana (Jpn), Christian Cevaer (Fra), Gary Emerson, John Daly (USA), Robert Allenby (Aus), Jay Haas (USA), Tetsuji Hiratsuka (Jpn), Tiger Woods (USA), Scott Barr (Aus)

71 Brendan Jones (Aus), Nick Price (Zim), Chris DiMarco (USA), Shigeki Maruyama (Jpn), Paul Broadhurst, Ignacio Garrido (Spa), Stuart Appleby (Aus), (x) Steven Tiley, Darren Fichardt (Rsa), Ian Poulter, Rory Sabbatini (Rsa), Mike Weir (Can), Mark O'Meara (USA), Spike McRoy (USA), David Toms (USA), Mark Foster, Todd Hamilton (USA)

72 Mark Calcavecchia (USA), (x) Nick Flanagan (Aus), Davis Love III (USA), Rodney Pampling (Aus), Chris Riley (USA), Stewart Cink (USA), Bo Van Pelt (USA), Barry Hume, S.K. Ho (Kor), Chad Campbell (USA), Tim Herron (USA), Brian Davis, Lee Westwood, Jonathan Cheetham

73 Scott Drummond, James Kingston (Rsa), Andrew Oldcorn, Phil Mickelson (USA), Kim Felton (Aus), Bob Estes (USA), Jyoti Randhawa (Ind), Paul Wesselingh, Martin Erlandsson (Swe), Sean Whiffin, Klas Eriksson (Swe), Adam Scott (Aus), Stephen Leaney (Aus), Tim Clark (Rsa), Greg Norman (Aus), Keiichiro Fukabori (Jpn), Jim Furyk (USA), Zach Johnson (USA), Tom Lehman (USA)

74 Brad Faxon (USA), Craig Perks (Nzl), Richard Green (Aus), Jonathan Kaye (USA), Thomas Bjorn (Den), Euan Little, Hennie Otto (Rsa), Glen Day (USA), Arjun Atwal (Ind), Aaron Baddeley (Aus), Miles Tunnicliff, Jean Francois Remesy (Fra) Sven Struver (Ger), Miguel Angel Jimenez (Spa), Louis Oosthuizen (Rsa), Daniel Sugrue, Stephen Ames (Can)

75 David Griffiths, Luke Donald, Paul Sheehan (Aus) Sergio Garcia (Spa), Charles Howell III (USA), Paul Bradshaw, Simon Dyson, John Huston (USA), Jerry Kelly (USA), Phillip Price, Steve Flesch (USA), Ben Curtis (USA), Cameron Beckman (USA), Fredrik Jacobson (Swe)

76 Andrew Buckle (Aus), Craig Parry (Aus), Hidemasa Hoshino (Jpn), Bob Tway (USA), Padraig Harrington, Peter Lonard (Aus), Nick Faldo, Anders Hansen (Den), (x) Brian McElhinney

77 Peter O'Malley (Aus), Frank Lickliter II (USA), Eduardo Romero (Arg), Adam Le Vesconte (Aus)

78 Paul Lawrie, Jimmy Green (USA), David Howell, Peter Hedblom (Swe)

79 Graeme McDowell, Ian Spencer, Yoshinobu Tsukada (Jpn), Matthew Hazelden

80 Tom Weiskopf (USA), Dinesh Chand (Fij), Andrew Willey

85 Neil Evans

86 Brett Taylor

Ret David Duval (USA)