Watch: Duke's eagle

Ken Duke makes an eagle on the par-4 16th after holing out from the fairway.

No one had ever shot a 29 on the back nine at Pebble Beach in the storied history of the AT&T Pebble Beach National Pro-Am -- until Ken Duke did it Thursday.

Actually, he finished with a 28. And it could have been even lower.

Duke's torrid run began on the par-4 10th with a birdie. After parring the 11th, he went on a birdie binge that didn't end until he got to the par-4 16th. Instead of a birdie, Duke jarred his approach for an eagle (watch video above). The eagle is just the second at the 16th in the last 20 years.

Duke nearly birdied the 17th: His birdie putt from the fringe just slipped over the cup. He then birdied the par-5 18th after laying up, then pitching to 10 feet.

Duke's 64 is good for the early lead at the AT&T Pebble Beach National Pro-Am.

Duke's scorecard: