After a slow start, Bjorn set a tournament record with six straight birdies on Nos. 11-16, propelling the Dane to a 5-under 67 during the third round at Wentworth. At 15-under 201, he leads by five over Luke Donald, a winner here in both 2011 and 2012, while Rory McIlroy lurks two shots further back in a tie for fourth.
Bjorn began the day tied for the lead with Shane Lowry, but he stumbled out of the gates, making a double-bogey 6 on the opening hole and adding a bogey at No. 5. He was 2 over on his round through 10 holes before his birdie streak allowed him to catch and pass Lowry, who sits alone in third place through 54 holes.
"It just became one of those days where things roll your way," Bjorn said. "I'm proud of the way I handled my round. To be 3 over after five holes and then shoot 67 was pretty good."
Bjorn shot a 30 on the par-37 back nine en route to a course-record 62 during the opening round, and he again shot a 30 on the inward half Saturday after closing with a birdie on No. 18. He is in search of his 16th career European Tour win, and third within the last nine months.
Donald is no stranger to success at Wentworth, and he appears to be headed for a sixth top-10 finish at this event since 2007. The Englishman shot a bogey-free 68, capping his round with birdies on Nos. 17 and 18 to earn a spot in Sunday's final pairing.
"It probably wasn’t that interesting to watch at home, but any time you play this course without making any mistakes, that’s fun," Donald said. "Obviously to birdie the last two, though, was a big momentum shift for me. It got me into the last group tomorrow, which is where I want to be.”
Playing this week after publicly announcing his breakup from former fiancee Caroline Wozniacki, McIlroy shot a 3-under 69 despite opening with a double bogey on the first hole. He is now in position for a career-best finish at Wentworth, after only one top-10 finish and three missed cuts in six prior appearances.
World No. 3 Henrik Stenson overcame a slow start to shoot a 1-under 71, and the Swede will begin the final round at 6 under, tied for seventh. Stenson has a chance to move to No. 1 in the world rankings with a high finish Sunday, but his chances hinge on how top-ranked Adam Scott plays this week at the Crowne Plaza Invitational on the PGA Tour.
The only player to best Bjorn's third-round score of 67 was Francesco Molinari, who fired a 7-under 65. The Italian began the day 11 shots off the pace, but he now will start the final round alongside Stenson in a tie for seventh.