Some of the top players faltered Thursday, with Masters champion Angel Cabrera and newly-elected Hall of Famer Jose Maria Olazabal each shooting 2-over 74 and John Daly at 1-over 73. Players Championsip winner Henrik Stenson shot 78.
Horsey and Wall each birdied four holes on the back nine; Fernandez-Castano finished birdie-eagle.
Charl Schwartzel, Niclas Fasth, Ross Fischer, Barry Lane and defending champion Miguel Angel Jimenez were at 68. Paul Casey, Robert Karlsson, Colin Montgomerie and 2003 British Open champion Ben Curtis were among a group of players at 69.