CHICAGO (Ticker) -- Threes were wild for Bob Gilder. Gilder carded a 3 on each of the final seven holes Saturday, finishing with a course-record 9-under-par 63 and taking a one-stroke lead into Sunday's final round of the SBC Senior Open.

Gilder's lowest score on the elder circuit set the mark for the Port course at Harborside International. After making three birdies on the front nine, he went birdie-par-birdie-par-birdie-birdie-eagle coming in.

The fantastic finish moved Gilder to 11-under 133, one shot better than Bobby Wadkins and three in front of John Mahaffey and Dick Mast.

"I figured something out on the practice tee and the momentum just built as the round went along," Gilder said. "I knocked the flag down on two of the last three holes. Everything fell into place."

That included a 25-foot putt on the par-5 18th hole that followed a pair of 3-woods and found the bottom of the cup, giving Gilder the lead.

Gilder's closing rush began at the par-4 12th, where his 9-iron approach stopped three feet from the cup. He parred the par-3 13th and 15th holes around a 10-foot birdie at the par-4 14th.

On the par-4 16th, Gilder again used a 9-iron approach and hit the flagstick before tapping in another three-footer. His pitching wedge on 17 also hit the stick and left him with an 18-inch birdie.

After winning twice in his rookie season on the Senior Tour, Gilder has been unable to break through this year. However, he has been showing signs of late, closing with a 63-64 and finishing fifth at the Canada Senior Open.

Wadkins also played bogey-free, opening and closing with consecutive birdies. Another second-year player, he won the 2001 Long Island Lightpath Classic.

Mahaffey also had a bogey-free 65 with a finish similar to Gilder's. He was 1-under through 10 holes before holing birdies at six of the last eight holes.

Mast shot a 64 that included 10 birdies, including six in a row from Nos. 8-13.

First-round leader Ted Goin was one of the few players over par, carding a 73 that left him six shots off the pace.

Defending champion Dana Quigley used a 7-iron from 163 yards for a hole-in-one on the 13th. A 69 left him at 3-over 147 and out of contention.

Instead, the field will be trying to track down Gilder, who has positioned himself for the $217,500 first prize.