Tiger Woods has carded a four-under-par 67 to share the lead with Mark Wilson after two rounds of golf's BMW Championship at Cog Hill.
The American pair are one stroke ahead of Irishman Padraig Harrington, South African Rory Sabbatini, Australian Marc Leishman and American Bo Van Pelt.
Sabbatini, who shared the first-round lead with American Steve Marino, had a three-shot advantage when he turned at eight-under but dropped two shots on his inward nine.
