Montgomerie had great expectations for this year following his standout performance at the Ryder Cup at the end of last year, but his stay in the U.S. has not borne results. He made just one cut in six weeks and never broke 70. He shot 72 and 73 at the Players Championship and missed the cut by a shot.
Guy Kinnings of IMG told the BBC: 'Monty is disappointed to let down the BellSouth Classic, but he just wants to recharge his batteries and to spend some quality time alone working on his game.
'He has spent a lot of time in America and believes it would be better to be at home for a week, before flying back for the Masters.'
He took two months off in the off-season to work on his strength to improve a troublesome back problem. He also swapped clubs, going from Callaway to Ben Hogan.
His place in the BellSouth has been taken by fellow Scot Paul Lawrie.