Nicklaus, Rodriguez in Playoff : Golf: Chi Chi’s birdie at 18th and Jack’s birdie at 17th help push U.S. Senior Open to extra day.

Jack Nicklaus beat one rival, Lee Trevino, in the final scheduled round of the U.S. Senior Open Golf Championship, but his work isn’t done yet.

Now he has to deal with an inspired Chi Chi Rodriguez in an 18-hole playoff today over the famed Oakland Hills course.

Rodriguez, complete with his trademark make-believe sword-fighting act, slipped past Trevino and Al Geiberger to tie Jack Nicklaus on the 72nd hole of regulation play on Sunday.

He capped it with a magnificent, hooking five-iron approach that hopped four times before curling in about two feet from the cup for a birdie on the final hole at Oakland Hills.

“A hell of a shot,” said Geiberger, who finished third and was eliminated from the playoff by Rodriguez’s birdie. “I don’t know how he did it.”

Said Rodriguez: “I wanted to hook it into the opening to the green on the right and let it catch the ridge and run to the hole. That’s what it did.”

He tapped it in, went through his sword-fighting routine with the putter, then executed two deep bows to the laughing, cheering gallery.

Rodriguez, a four-time winner on the over-50 circuit this season, and Nicklaus each shot one-over 71s in the fourth round and finished 72 holes at 282, two over par on the unyielding 6,718-yard course of Oakland Hills Country Club.

Geiberger, with a round of 70, was at 283. Only a bogey on the 18th, where he drove into the rough, kept him out of the playoff.

Trevino, the third-round leader and defending champion, was paired with Nicklaus in the final twosome, but their anticipated head-to-head confrontation did not materialize.

“Both Lee and I struggled a little bit today,” Nicklaus said. “I think we got a little too serious.”

Trevino bogeyed the first two holes but was never far behind the leaders. He moved into a tie for the lead with a 30-foot, downhill birdie putt on the 16th, but lost his last chance for a successful defense when he missed the green and bogeyed the 17th.

He shot 74 and was tied at 284 with Jim Dent, who shot 67.

It was another two strokes to Don Bies and Charles Coody. Coody shot 71 and Bies 73.

Nicklaus, who has won four of eight starts as a senior, was in and around the lead most of the day--but was in serious danger of taking himself out of it on the par-five 12th.

He drove far to the right, then put his second shot behind a tree. His third clipped a limb and dropped straight down. He was on in four and had to two-putt to save bogey.

Critical, par-saving putts on three of the next four holes kept him in it, and he gained a share of the lead with a five-iron to five feet on the par-three 17th.

Looking over the putt, Nicklaus told his caddie: “I missed this very same putt to lose the Open last year. I’m not going to miss it this time.”

And he didn’t.

That put him two over. Moments later, Rodriguez made hit short putt at the 18th.

Nicklaus had a chance to win it outright with a birdie putt of about 14 feet on the 18th, but “I knew it was short as soon as I hit it,” he said.

“I was pulling for him to make it,” said Rodriguez, who watched from behind the 18th green.

“When he missed, it cost me $40,000. I was supposed to go to Maine for an outing tomorrow,” he said.

This will be the fourth playoff in the U.S. Senior Open, which was first played in 1980.