Paul Casey and Austin Cook lead by one, Luke Donald is in the mix for the first time in years and Dustin Johnson is lurking, just two strokes back.
In a statement released on Twitter, Garrigus says the drug that caused him to fail a test was marijuana.
The LPGA is in Arizona this week, and in addition to the desert heat, the players have had to contend with dangerous wildlife during the event.
Masters champ Patrick Reed was spotted on the range at the Valspar Championship with Tour swing guru David Leadbetter.
Gore has competed on the PGA Tour for more than 20 years. The USGA believes he and his team will help the association better communicate and synergize with Tour professionals.