Spieth had said earlier in the week that an encore means the show is over, and it sure didn't look that way at the Hyundai Tournament of Champions. He opened with seven birdies and no bogeys for a 7-under 66 that left him one shot behind when Reed finished strong and made a 15-foot eagle putt on the 18th hole for a 65.
Reed hasn't won since he rallied to win at Kapalua a year ago, though he hasn't been far off. He ended last year with six top 10s in five countries, and he showed his comfort level on a Plantation Course in gorgeous sunshine and only a stiff breeze that picked up in the middle of the round.
Reed and Spieth both had eagle putts on three of the par 5s.
The difference was Reed converting on the final hole. They were in the last group and part of a five-way tie for the lead when Reed smashed a 3-wood from 309 yards that trickled onto the front of the green and let the grain take it 15 feet below the hole.
"I didn't think I could get it all the way to the green," Reed said. "I thought if I smoked it, I'd get to the front edge and it just happened to ride the wind a little bit and kind of just kept on going. And once it gets on that green, I know it's going to just keep feeding."
That capped off a finish that took Reed from the middle of the pack to the lead. He was 6 under over the last six holes with that eagle.
Spieth came up some 60 yards short and hit a great shot of his own, a flip wedge that rolled to 4 feet for birdie.
Jason Day, who has a chance to replace Spieth at No. 1 in the world this week, has not played in three months since the Presidents Cup. And it showed. In ideal scoring conditions, Day didn't make a birdie until the ninth hole and made only two on the back nine for a 70.
Only seven players from the 32-man field of PGA Tour winners last year failed to break par. One of them was Dustin Johnson, a past winner at Kapalua, who had to birdie the 18th for a 73. Johnson had the longest drive on six of the holes, including three of them just short of 400 yards. It didn't help him score.
Smylie Kaufman, one of 14 players making their debut at Kapalua, hit the opening tee shot of 2016 so far left that he played his next shot from the ninth hole. He still made birdie and wound up with a 70.
Spieth won the Masters and U.S. Open last year, along with three other titles that led to the FedEx Cup and a sweep of all the awards. He wanted this to be a continuation of last year and brought that attitude to the opening tee shot.
"It's another event in the course of my career," he said. "The calendar changed."
It only took two holes from a familiar look -- Spieth walking across the green as a long putt dropped for birdie. He had long two-putt birdies on the par 5s on the front and missed a 15-foot eagle on the 15th that was such a weak attempt that he said even Reed said to him, "Nice effort."
They typically do well together, including a 2-0-1 record as partners in the Ryder Cup two years ago. Reed picked up his first PGA Tour victory in a playoff over Spieth in 2013 with a shot out of the trees to 3 feet. Spieth got him back last year at Innisbrook with a 30-foot birdie putt on the third playoff hole.
"Whether we want to feed off each other or we want to beat the crap out of each other, we somehow play well together," Spieth said.
Reed wasn't converting many chances, with two-putt birdies on the par 5s on the front. His round turned with a 15-foot birdie putt on the 13th. He followed with a pitch to tap-in range on the 14th and 15th holes and a shot over the gorge to 2 feet on the 17th.
Snedeker has been at Kapalua for a week, playing four times before the official start of tournament week. He was ready to go, and when it counted, he looked sharp.
"I know the golf course pretty well and I think getting over here early, the greens always pose a big problem," Snedeker said. "You get comfortable on greens and be aggressive on putts that you know are fast or slow. You just have to know putts. They're hard to read. So that's kind of the reason I came over to do that."