Bing Crosby's son Nathaniel overtook foundering first-round leader Gary Lipski and shot 70 to open a four-stroke lead over Marty West at the midway point of the 72-hole Middle Atlantic Golf Association Amateur tournament today at Woodholme.

Crosby, 20, last year's U.S. Amateur champion and a junior at the University of Miami, shot three under par on the 6,700-yard course, making five birdies en route to a two-day total of 142.

For the second day in a row he bogeyed his opening hole, missing a four-foot putt. Lapses in concentration resulted in a missed two-foot putt for par at the 13th hole and six-foot attempt at the 14th.

"I hit the ball pretty well but I got a little sloppy out there," said Crosby, who started the day two strokes behind Lipski and fell three shots back when he hit over the first green and bogeyed.

But Crosby caught up when he gained his second birdie after sinking a 20-foot at the fourth hole, and Lipski three-putted the slick green for double-bogey 6.

Crosby increased his lead with par on the ninth hole after Lipski hooked into water and then three-putted for triple-bogey 7. Lipski finished with 79 and is tied for fourth with Larry Zee (71) of Grand Island, N.Y., at 149.

West, the four-time winner of this event, equaled Crosby's 70 and stands at 146. David Abell of Fort Pierce, Fla., is third, 76 -- 148.

West, who was paired with Crosby in Thursday's opening round and shot 76, will get another chance to play Crosby face-to-face Saturday.

"I'm just glad to have shot myself back into the tournament," said the former Walker Cup winner. "It's great to have a player like Nathaniel here. I hope we can give him a run for his money."