Thomas, who won both Hawaii events past year, was well placed on four under with six holes remaining, but wild shots at 13 and 15 led to penalty drops and a pair of double-bogeys while he dropped another stroke at 17 before a birdie at the last saw him sign for a 75.
"I think the hardest part is going to be staying in the moment and recognizing that it's a new year", Thomas said as last year was ending.
Even though Johnson, Spieth, Thomas and Matsuyama are among those who won multiple times past year, winning is not getting any easier.More news: Liverpool's Salah back in training ahead of Manchester City clash
Fowler enters the week fresh off a win at the Hero World Challenge - an exhibition event highlighted by Tiger Woods' latest return to golf.
Fowler finished in the top 11 in three of last year's four majors, but faltered at some point over the weekend. I need to do that some more. That includes the 2008 U.S. Open, his 14th and most recent major.
Spieth, who takes pride in being a good closer, still couldn't shake the memory of losing a five-shot lead on the back nine of the Masters in 2016.
The Australian set the tone for his day with a five-foot birdie at the first hole en route to a six-under-par 67 at the Kapalua Plantation course on the island of Maui.More news: Traffic moving after hours-long interstate shutdown
"The unknowns are very exciting right now", Spieth said.
The two leaders will be wary of the presence of 2013 Kapalua champion Johnson after he recovered from a poor start to roll in seven birdie putts and card a 68. I'm the one that's out there, that's putting it on the line every single week.
"The swing feels really good and, mentally, I feel strong".
It starts at the Tournament of Champions on Thursday, where Ryan Armour - the oldest player in the field at 41 - hits the opening tee shot.More news: Dominion Energy, SCANA To Merge In $7.9B All-Stock Deal
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