In an out-of-the-ordinary day on the PGA Tour, first-round leader Camilo Villegas failed to qualify for the weekend action and the normally difficult PGA National course continued to yield low scores.
The center of attention, however, turned out to be McIlroy, the event's defending champion and the top-ranked player in the world.
He had already endured a struggling start to the season, having missed the cut in his first tournament of the year before losing in the opening round of the World Match Play Championship last week. Things, however, got worse on Friday.
After shooting an even-par 70 in the opening round, McIlroy played his first eight holes in 7-over on Friday. After hitting his second shot into the water at the par-5 18th, his ninth hole of the day, he shook hands with playing partners Ernie Els and Mark Wilson and walked off the course.
McIlroy told a group of reporters who caught up with him in the parking lot that he was "in a bad place right now."
An hour later a statement was released from McIlroy through the PGA Tour saying his withdrawal was brought on by a painful wisdom tooth that is "due to come out in the near future."
"It was very painful again this morning, and I was simply unable to concentrate," the statement said. "It was really bothering me and had begun to affect my playing partners.
"I came here with every intention of defending my Honda Classic title. Even though my results haven't revealed it, I really felt like I was rounding a corner."
While that was going on, Guthrie was in the process of firing a tournament-low, 7-under 63 that put him at 9-under 131 for 36 holes and one shot in front of Michael Thompson.
Guthrie, who reached the PGA Tour by finishing third on the Web.com Tour's money list last year, has now made the cut in five of his first seven starts on the circuit. He is trying to become the second rookie to win on the tour this year after Russell Henley, who captured the Sony Open in Hawaii.
It took a score of even-par 140 to make the cut and that was what Woods turned in after his second straight 70. Villegas, who shot a 64 on Thursday, posted a 77 Friday and missed the cut for the third time in four starts this year.
McIlroy is scheduled to play next week at the World Golf Championship event that will be played at the Doral Country Club in Miami.