UPDATE 1-Golf-Superb 63 a relief for Retief after early shock

* Goosen leads after recovering from first-hole howler

* Second-placed Scott leads strong Australian challenge

(updates at end of round)

By Tony Jimenez

LOCH LOMOND, Scotland, July 10 (Reuters) - Retief Goosen duffed his first shot like a weekend hacker before proving his pedigree with an eight-under-par 63 to sail into a two-stroke lead in the Scottish Open second round on Friday.

The 40-year-old South African hit seven birdies and an eagle after recovering from the surprise of dribbling a 180-yard drive into the rough at the par-four 10th, his opening hole.

Goosen, the Loch Lomond course-record holder after firing a 62 in 1997, finished with a total of 11-under 131. Adam Scott (67) was in second place on 133, one ahead of fellow Australian Marcus Fraser (66) and Germany's Martin Kaymer (65).

"I was trying to hit a three-wood off the tee at the 10th and hit a low, thinny one going right," the 2001 and 2004 U.S. Open champion told reporters at the warm-up event for next week's British Open at Turnberry.

"It was a bit of a weird start, a bit of a shock. My playing partners (Australian world number six Geoff Ogilvy and Britain's Oliver Wilson) kept quiet but I'm sure they were laughing."