Funk predicted Saturday that he'd have to make his move on the front nine and then just hold on. He did neither, failing to cut into the deficit and then watching his quest to become the fifth straight come-from-behind winner die on 13, where his 3-wood headed straight for the thigh-high grass on the left.
Instead of knocking it onto the fairway with a wedge or 9-iron, Funk tried to get more distance out of the shot with a 7-iron.
"I thought I would maybe have a better shot at maybe getting up and down and getting, at worst, a 5 out of it," Funk said. "I thought wrong."
The ball traveled less than 20 yards and stayed in the rough.
"And from there was a debacle the rest of the way," said Funk, who three-putted.
Mark McNulty (68) finished in third, five shots back. Norman shot a 70 and finished in fourth, his third straight top-5 finish.
Norman, the 53-year-old Australian who held the 54-hole lead at the British Open two weeks ago, is skipping the PGA Championship at Oakland Hills next week. His honeymoon with tennis great Chris Evert over, he said he needs to return to work as CEO of Great White Shark Enterprises.
"You won't see me until December," Norman said, referring to the Merrill Lynch Shootout at the course he designed at the Tiburn Golf Club in Naples, Fla.
Norman never found a rhythm in the Rockies and grumbled about the inconsistent greens and sometimes perilous pin placements.
"The golf course was just awkward," he said. "It was just inconsistent."
Romero, one of the big hitters on the Champions Tour who regularly hits driver-wedge into the par-4s, is the first international winner at the U.S. Senior Open since Australia's Graham Marsh in 1997 and the first to hold both the 54-hole lead and the trophy since Bruce Lietzke in 2003.
Although several deer and fawn showed up Sunday on the cragged course carved out of the Rocky Mountain foothills, there weren't any more sightings of black bears like the one that interrupted the tournament Friday.
Volunteers did arrive at dawn to discover a bear had visited the concession stand at the seventh hole overnight and helped itself to a smorgasbord of candy bars, bananas, hot dogs and bread.
And a doe and two fawns crossed the 14th fairway Sunday, where Norman hit a long drive over them and Juan Quiros had to wait as the deer trotted off into the trees.
Other than that, the only interruption of the final round was a 23-minute weather delay when the leaders were on the fairway on the sixth hole.