A dazzling run of five straight birdies at the end of the second round gave Argentine Ricardo Gonzalez a second successive seven-under 65 and a one-stroke lead at the Johnnie Walker Championship in Scotland on Friday.
Austrian Bernd Wiesberger (66) was in second place on 131, two ahead of British pair Mark Foster (67) and Tommy Fleetwood (65) at Gleneagles, the venue for next year's Ryder Cup.
"I don't think I have ever shot 65 two days in a row," the 43-year-old Gonzalez told reporters as he chased the fifth European Tour victory of his career.
"I am excited about the weekend and will try to keep doing exactly the same things I have been doing for the past two days. If I can do that I have a great chance to win again."
Italy's Francesco Molinari was six strokes off the pace after carding a 67 while Ryder Cup team mate Paul Lawrie was on 137 following his 67.
Ryder Cup captain Paul McGinley returned a 71 for 139 while his predecessor as skipper, Jose Maria Olazabal (68), was down the field on 141 and just made the cut.