World No. 1 Dustin Johnson carded a 9-under-par 63 to move to 13-under overall and take a one-stroke lead over Brooks Koepka at the halfway stage of the WGC-HSBC Champions.
Johnson birdied the last four holes for a back-nine 29 at Sheshan International in Shanghai, the same course where he won in 2013 by shooting a four-day aggregate record of 24-under-par 264.
Last season on the PGA Tour, Johnson won a career best four times including three tournaments in a row – Genesis Open, WGC-Mexico Championship and WGC-Dell Technologies Match Play Championship. He also won The Northern Trust during the FedExCup Playoffs.
Malaysia’s Gavin Green meanwhile fell from second spot to joint 12th after a second round 74. The current Asian Tour Order of Merit leader had opened with a seven-under-par 65 in his debut appearance in a World Golf Championships event.