Joe Durant stormed into the lead after the second round of the Bob Hope Classic.
He fired a superb 11-under par 61 at the Indian Wells course to take a three-stroke advantage in the five-round event.
Durant birdied his last six holes to close on an 18-under-par 126 after his opening 65.
He said: "When you keep getting the ball close, good things are going to happen, and they did today."
Durant's 36-hole score was a new record for the event, which began in 1960.
Fellow American Chris Smith, who lost his Tour card last season, was second at 15-under 129 after carding a 64 at Bermuda Dunes.
Mark Calcavecchia, Bob Tway and Spain's Miguel Angel Jimenez share third on 14 under par with Kevin Sutherland, Glen Day and Paul Stankowski all a stroke further back on 13 under.
Tournament favourite David Duval is handily placed on 11 under par but Jose Maria Olazabal had plenty of ground to make up on four under par.