Defending Open champion Todd Hamilton will need a change in fortune if he is to retain the Claret Jug after firing an opening 74 to finish two over.
The American, who won a play-off at Royal Troon, was in big trouble after making three bogeys and a double bogey.
But three birdies at the last four holes saved his round.
Former champion Ernie Els and world number four Phil Mickelson also finished two over after struggling on the back nine at St Andrews.
World number three Els was unable to build on a promising start.
Els, the 2003 champion and 2004 runner-up, carded birdies at the third and fourth but a bogey six at the par-five fifth saw his fortunes change.
Three successive birdies from the 11th saw him slip into the black and he was unable to recover despite setting up several promising positions.
"I was in too many bunkers. I made too many mistakes," he said.
Mickelson reached the turn at two under but dropped a shot at the 12th before his round fell apart with a triple bogey at the 15th.
Another bogey followed at the 17th before a birdie at the last gave him something positive to think about overnight.