(Reuters) - Justin Thomas, hunting his third victory of the young season, eagled the par-five last to set a PGA Tour record for 36 holes and stretch his overnight lead to five shots after the second round of the Sony Open in Hawaii on Friday.
Three strokes clear after opening with a magical 11-under-par 59, the American world number 12 followed up with a six-under 64 on another benign day of ideal scoring conditions at Waialae Country Club in Honolulu.
The long-hitting Thomas, a winner in two of his last three PGA Tour starts, also recorded seven birdies and three bogeys to post a 17-under total of 123 in the first full-field event of the year on the U.S. circuit.
Despite finding the left rough off the tee at the par-five 18th, he struck a superb second shot from 205 yards to nine feet and coolly sank the eagle putt to post a landmark total at the tournament's halfway mark.
Thomas' 36-hole aggregate eclipsed the previous low of 124 jointly held by Pat Perez (2009 Bob Hope Classic), David Toms (2011 Crowne Plaza Invitational) and Jason Day (2015 BMW Championship).
Fellow American Gary Woodland, who is also known for his prodigious length off the tee, was alone in second place after carding a second successive 64.
Olympic champion Justin Rose (64) was a further two strokes back at 10-under, tied for third with Americans Hudson Swafford (68) and Zach Johnson, who fired a best-of-the-day 61.
Thomas, who became only the seventh player to break 60 on the PGA Tour, birdied two of the first seven holes on Friday before he bogeyed the eighth after pulling his tee shot left into a treeline.
He then rebounded with a run of four birdies from the ninth to stretch his lead to five strokes before he ran up another bogey at the par-four 13th, where he bunkered his approach.
(Reporting by Mark Lamport-Stokes in St. Augustine, Florida; Editing by Peter Rutherford)