American D.A. Points quit before he teed off at his first hole, citing a back injury, while his countryman Hunter Haas pulled out after just three holes, with the same ailment.
England's Simon Dyson also succumbed to a bad back after shooting a four-over par 76.
Another Englishman, Paul Casey, withdrew with a shoulder injury after reaching the turn at six-over par.
Argentine Angel Cabrera, the former US Open and Masters champion, cited "personal reasons" for his early departure, organisers said.
Cabrera found the water three times on the 'island green' par-three 17th hole where he shot a nine to complete his round at six-over.