Hampshire Motor Speedway and had his winning time tossed out for yet another infraction. He'll start first in Sunday's Overton's 301 (3 p.m. ET, NBCSN, PRN, SiriusXM NASCAR Radio) on the 1.058-mile track.
Martin Truex Jr. will start first on Sunday.
"Not the way we wanted to get our first pole of the year, but looking forward to starting up front and getting a good pit stall", said Truex. Larson had initially taken first place in Friday's qualifying, but his speed was disallowed after his vehicle failed post-qualifying inspection for an unapproved rear decklid fin. NASCAR said there would be no additional penalties. He turned a fast lap of 133.324 miles per hour.
Larson held a one-point lead over Truex and the penalty, dropped him down to second place, 34 points behind. It was his first significant racing since crew chief Chad Johnston received a three-race suspension and the team was docked 35 points for failing a post-race inspection last weekend.
Ganassi did not appeal the penalty. Tony Lunders is serving as interim crew chief.
Former crew chief and current NASCAR on NBC analyst Steve Letarte explains how Larson's vehicle was deemed legal and then illegal in a matter of hours and a handful of laps. "I don't know. We'll work on it and get it better".
According to NASCAR, the rear deck fin lid passed pre-qualifying inspection, but was considered out of spec in post-race qualifying.
Larson also started in the rear because of inspection issues at Kentucky Speedway.
It's the fifth career pole for Larson, including four during the current season. Truex's Furniture Row Racing No. 78 Toyota will lead the 39-car field to green after claiming the Coors Light Pole in Friday qualifying.
Martin Truex Jr. was second, followed by Jimmie Johnson, Matt Kenseth and Jamie McMurray.
"This is the continuation of what we started in 2015, when we started figuring things out as a group. I should close my eyes in Q more often", Johnson tweeted.