Jacobson shot a flawless six-under 66 Friday to extend his bogey-free streak to 29 holes and take the 36-hole lead at the WGC - HSBC Champions.
The Swede notched his first PGA Tour win earlier this year at the Travelers Championship, his first victory since three championships on the European Tour in 2003. He currently stands at 11-under 133, one shot better than former British Open champ Louis Oosthuizen and Adam Scott at Sheshan International Golf Club.
Last week, Jacobson had an excellent performance at the CIMB Asia Pacific Classic Malaysia, but fell well short of Bo Van Pelt, who also put himself in contention this week. It was Jacobson's first top-10 finish since his lone win this year, and now he's in line for another, if not better.
Oosthuizen tied a course record with a bogey-free nine-under 63, putting him at 10-under 134 and in a share of second with Adam Scott (65). Scott is the leader on the non-European Tour member money list, amassing nearly two million euros in only seven tournaments.
First-round leader Keegan Bradley started with an eagle and a birdie in his first four holes, but didn't post another birdie until the last in a round of two-under 70. He sits alone in fourth place at nine-under, only two shots off the pace.
Van Pelt (69) is aiming for his second straight win and shares fifth with Paul Casey (66) at eight-under 137. Martin Kaymer (68), Aaron Baddeley (68), Thongchai Jaidee (69) and Lee Westwood (68) are tied for seventh at minus- seven.
MORE TO FOLLOW.