Leading scores after Thursday's opening round of the US PGA Northern Trust at TPC Boston (par 71, USA unless noted): 64 - Harris English, Kevin Streelman, Cameron Davis (AUS), Russell Henley 65 - Louis Oosthuizen (RSA), Charley Hoffman, Scott Piercy, Bubba Watson, Kevin Kisner, Sebastian Munoz (COL), Matthew Wolff 66 - Ian Poulter (ENG), Talor Gooch, Daniel Berger, Robby Shelton, Charles Howell, Danny Lee (NZL), Adam Scott (AUS), Tommy Fleetwood (ENG) 67 - Maverick McNealy, Harry Higgs, Dustin Johnson, Tyrrell Hatton (ENG), Cameron Tringale, Rickie Fowler, Lee Kyoung-hoon (KOR), Brian Harman, Mark Hubbard, Ryan Palmer afp