Korean KJ Choi took a one-stroke lead over Swede Richard Johnson into the third round of the Nordea Scandinavian Masters.

But it is Open champion Louis Oosthuizen's bid for a second straight victory which has given the event an added dimension.

Nobody in the history of the European Tour has won The Open and then tasted success again on the circuit a week later.

But Oosthuizen, honouring a commitment to play in the tournament after seeking an invitation prior to his runaway seven-shot triumph at St Andrews, resumed in joint third place and only two behind Choi.

The 27-year-old, who led from the second round onwards last week, was two in front after two early birdies yesterday, but went into the water for a double bogey five at the 17th and added 'only' a 70 to his opening 67.

That allowed Choi, seven times a winner in America but with just the 2003 German Masters to his name in Europe, to take charge on nine under.

The 40-year-old's putting remains a concern, though. Two weeks ago he revived memories of the great Sam Snead by turning to face the hole and trying a "side-saddle" style, but while he is back to a normal action this week he has missed a host of chances.

Most of Europe's stars are taking the week off, but Italian Edoardo Molinari, winner of the Scottish Open a fortnight ago, is in seventh place at halfway.

If Molinari can finish first or second tomorrow he would join his brother Francesco in an automatic qualifying spot for October's Ryder Cup.

Luke Donald is currently fourth, but he would be the one to drop out of the top nine with five weeks in the race to go because of how the side is selected - four based on world ranking points and then five from their European Tour rankings.