Clarke finished with an eight-iron into the ninth hole for an eagle two and a 70, but McGinley withdrew before the start with a bad back.
Peter Lawrie (73) and Simon Thornton (76) -- who replaced McGinley in the field -- had a disappointing day at the office.
Ryder Cup captain Jose Maria Olazabal also struggled, managing only a 75 on his return to action. Fisher was part of the victorious European side in Wales two years ago, but has managed only one top-five finish since then and finds himself down at 140th in the world.
"It's been a tough season," the 31-year-old Englishman said, "but it's nice to see my hard work pay off, and if that Ryder Cup win doesn't inspire you then nothing will."
The closest he came to winning this year was the Wales Open in June. He was one behind with four to play, but was then given a one-stroke penalty for slow play and dropped to sixth.
Gallacher, meanwhile, was still in contention for the Dunhill Links Championship at St Andrews on Sunday when he played the wrong ball on the 16th and ran up a quadruple-bogey eight. Keeping a bogey off his card next time out was a fine effort by the 37-year-old, nephew of ex-Ryder Cup captain Bernard Gallacher.
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