American Harris English clung to a two-stroke lead after Friday's second round of the WGC St. Jude Invitational despite strong charges into second by Australian Cameron Smith and Mexico's Abraham Ancer.

English, chasing his third title of the year, followed an opening 62 with a five-under par 65 to stand on 13-under 127 after 54 holes at TPC Southwind in Memphis, Tennessee.