Clark has two-stroke lead at Colonial

FORT WORTH , Texas, May 30 (UPI) -- Tim Clark enhanced his bid for his first PGA Tour win by shooting a 4-under 66 Saturday for a two-stroke lead at the Crowne Plaza Invitational in Texas.

Clark finished his third round with a 19-foot birdie putt on the 18th hole to go to 17-under 193.

The 33-year-old South African has earned more than $12.7 million in 183 tournaments without winning on the PGA Tour.

Four-time PGA Tour winner Steve Stricker (69), Steve Marino (62) and 21-year-old Australian Jason Day (65) are tied for second at 15-under 195.

Vijay Singh (69) is fifth at 13-under 197, and Justin Leonard (64) and Woody Austin (67) are tied for sixth at 12-under 198.

Phil Mickelson, the 2008 champion at Colonial, is off the PGA Tour to be with his wife Amy, who is battling breast cancer.