Toms, who won the inaugural playing of this event five years ago, has only one top 25 finish to his credit in 2008.

He made eight birdies and three bogeys at the Quail Hollow Club and had a one-shot lead over Phil Mickelson and Jason Bohn.

After missing the green at his final hole, Mickelson chipped in from 25 feet for a birdie and a 68.

"It was a good day," said Mickelson, playing for the first time since his fifth-place finish at the Masters. "It's good to see some positive results from the time I spent the last couple weeks."

Zach Johnson, Ben Curtis and Camilo Villegas were among those at 69. Adam Scott, the winner last week at the Byron Nelson Classic, shot a 72.

Masters champion Trevor Immelman, who missed the cut at the Nelson, stumbled to a 76.

Defending champion Tiger Woods is out of action after having undergone knee surgery.