England's John Parry, winner of his first European Tour title only two weeks ago, charged five strokes clear of the field with a superb seven under par 65 at St Andrews.
The 23 year old Challenge Tour graduate, a team-mate of Rory McIlroy at the 2007 Walker Cup, left nine members of Europe's Ryder Cup Team - McIlroy included - trailing in his wake with seven birdies in the windy and murky conditions.
Parry, in the first group out, stood 12 under par, with big-hitting Spaniard Alvaro Quiros seven under.
Graeme McDowell, Ross Fisher and Martin Kaymer are joint third with Dane Thomas Björn and Scot Martin Laird one further back.
The cut to the leading 60 comes after Saturday's third round, with three courses being used for the celebrity pro-am.
Damien McGrane is twos shot further back on three under after a round of 69.
Darren Clarke carded a 67 to move up to one under.
Michael Hoey remains level par after signing for a 73.
Rory McIlory and Paul McGinley are one over par.
Peter Lawrie finished with a 76 and a two over par total.
Simon Thornton is three over after a round of 74.
Shane Lowry finished with a 78 to fall back to 3 over par.
Gareth Maybin and Gary Murphy are both four over par.
