Leading scores after Thursday's first round of the US PGA Tour's Safeway Open at Silverado Country club in Napa, California (par 72, USA unless noted, halted by darkness with 15 players to finish round on Friday): 63 - Russell Knox (SCO) 64 - Sam Burns, Cameron Percy (AUS), Bo Hoag 65 - Brendan Steele, Pat Perez 66 - Tom Hoge, Scott Harrington, Akshay Bhatia, Andy Zhang (CHN) 67 - Stewart Cink, DJ Trahan, Tim Wilkinson (NZL), Brian Stuard, Patrick Rodgers, Carlos Ortiz (MEX), Charley Hoffman, Chez Reavie, Harold Varner afp