Marco Dawson took a major step towards retaining his Tour card with a bogey-free seven-under-par 64 in the opening round of the Texas Open in San Antonio.

Dawson, who turns 38 next month, holds a one-stroke lead over Jay Williamson and defending champion Justin Leonard at the LaCantera Golf Club.

Dawson, who will hold on to his card if he finishes in the top three, said: "I drove the ball well and putted well. It was a lot of fun." Brandel Chamblee, Scott McCarron, Carl Paulson and Bob Burns are two shots back.

Sweden's Jesper Parnevik, Steve Elkington of Australia and rookie Briton Luke Donald head a group of 15 that opened with 67s.

This tournament is one of only five events remaining for players seeking berths in the season-ending Tour Championship, which is open to the top 30 on the money list.

Yet, with the Ryder Cup cancelled in the wake of the terrorist attacks on the United States, most of golf's elite players have skipped the event. Among those who have opted out are Tiger Woods, Phil Mickelson, Vijay Singh, Sergio Garcia and David Duval.

David Toms, fifth on the money list, is the only one among the top 10 entered this week.