Zach Johnson is one of the most serene guys on the PGA Tour, so the news that he suffered a first-rate meltdown at the Dean & DeLuca Invitational is more than a little surprising.

Johnson was 1-over par on his round at the par-4 12th when he was notified by an official that he was being put on the clock for slow play, and the two-time major champion lost it.

Zach Johnson with a major meltdown after being put on the clock. Dumped all his clubs out of the bag! pic.twitter.com/KDJleSu8vC — Michael Martin (@michaelmartinut) May 27, 2017

The 41-year-old dumped his clubs all over the fairway, then proceeded to make a double-bogey six.

He would make back-to-back bogeys at the 13th and 14th en route to a 5-over-par 75.

Here's the carnage on 12. I need this footage like I need air. pic.twitter.com/WVZXPFsno9 — No Laying Up (@NoLayingUp) May 27, 2017

The temperature reached over 90 degrees Saturday in Fort Worth, Texas, so maybe the heat got to him.