McCord, a two-time Senior Tour winner and a sometimes irreverent golf analyst for CBS Sports, knocked an 8-iron to a foot for a birdie at the 14th to take a two-shot lead over Murphy, who was just finishing his round.
But McCord hooked his drive against rocks at the par-4 16th and was forced to play his second shot out to the fairway. Though he found the green with his third, McCord three-putted for a double-bogey six that dropped him into a tie with Murphy. He parred the final two holes for a 1-under 71.
'You have good days and bad days and the key is to manage things out there,' said McCord, who at 26th on the season money list is eligible to play in next week's season-ending Senior Tour Championship, an event he won in 1999.
McCord fired a course-record-tying 63 to grab the lead in Friday's opening round. The 9-under-par score was his best on the Senior Tour and matched his low round on the PGA Tour.
Murphy, a broadcaster for NBC Sports, began the day five strokes behind McCord and fell further off the pace with a bogey at the second hole. He erased the mistake with a birdie at the third then hit a 4-iron to a foot to set up an easy birdie at the 209-yard 5th.
After making it back-to-back tap-in birdies with a sand-wedge approach tight to the sixth hole, Murphy wrapped up the front nine in fine fashion with a 12-foot birdie putt at the eighth followed by a 25-foot chip-in for eagle at the par-5 9th.
Murphy moved to 10-under with a birdie at No. 11 but dropped a shot at the 12th. He lipped out birdie tries at Nos. 16 and 17 but found the mark with a 20-foot birdie putt at the par-5 closing hole.
'I got a new set of irons,' said Murphy, who hit 16 of 18 greens in round two. 'I started using these new clubs last week...I trust them a little more this week.'
Murphy, 58, amassed 11 wins in his first five seasons on the Senior Tour. His last victory came at the 1997 Toshiba Senior Classic and his best finish this year was a tie for 13th at the Senior PGA Championship in late May.
'My year has been crummy,' he said. 'I haven't played well at all. I putted mediocre and my confidence just wasn't there.'
Gilder, whose win at the Verizon Classic in February was just his third start as a member of the 50-and-over circuit, shot 67 to get to nine-under 135. Fleisher, currently second to Allen Doyle in 2001 earnings, had a 69. Tewell turned in a 68.
Jim Barker carded a 65 to join Larry Nelson, who had 69, at eight-under 136.
Doyle heads into the final round four off the pace at 138. A total of 27 players finished 36 holes within six shots of the lead.
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