Zach Johnson is tied for the lead at the John Deere Classic

Zach Johnson, Rory Sabbatini and Brian Harman shot 8-under-par 63s Thursday to share the lead after the first

round of the John Deere Classic.

Johnson and Sabbatini played bogey-free golf, while Harman had nine birdies and one bogey on the par-71 TPC Deere Run.

They led 2004 British Open champion Todd Hamilton, Australian Steven Bowditch andWilliam McGirt, the best afternoon finisher, by a stroke.

Johnson, who won the Deere in 2012 and lost it to Jordan Spieth in a playoff last year, birdied four of his first five holes and was 6

under on his opening nine.

Harman, who bettered his best round of the year by two strokes, was 2 under through six holes when his caddie, Scott Tway, took ill. Jay

Hatch of Davenport, Iowa, a high school basketball coach, volunteered from the gallery, and carried Harman's bag the last 12 holeswhich

Harman played in 6 under.