GREENVILLE, S.C. — David Zabriskie won his fourth straight U.S. Cycling time trial title Saturday, as Floyd Landis was eighth as he tries to make a comeback from a doping suspension.

Zabriskie finished the 20.7-mile course in 39:37, beating Tom Zirbel by 44 seconds.

Landis served a two-year suspension for testing positive for synthetic testosterone, which stripped him of his 2006 Tour de France victory. He finished in 46:30.

Zirbel picked up his second straight second-place finish at 40:21, while Scott Zwinsanski was third at 41:18.