By Andrew Both
SHANGHAI (Reuters) - Northern Irishman Graeme McDowell extended his lead to three strokes after the second round of the $8.5 million WGC-HSBC Champions tournament on Friday.
McDowell carded a second successive 67 to post a 10-under 134 halfway total on an overcast day at Sheshan, while Englishman Ian Poulter (67) picked up four birdies in the final five holes to vault into second place on seven-under.
American Bubba Watson and Japan's Hiroshi Iwata were equal third on six-under in the only World Golf Championships event played outside the U.S.
(Editing by Patrick Johnston)