In preparation, he has made some changes, such as adding Jim "Bones" Mackay to the bag. Mackay was Phil Mickelson's longtime caddie, and he'll make his full-time return to carrying the bag after a run as an announcer.
Thomas also made it clear on Instagram that he's putting in some work in the gym, too.
Oh, and this brought out the jabs.
First on the tee, LPGA pro and former U.S. Women's Open champion Michelle Wie West.
And, of course, if is workout-related, you just know Bryson DeChambeau was going to weigh in. DeChambeau has gone through a well-documented body change, adding 40 pounds of muscle to increase his swing speed and add distance -- a lot of distance -- to his game.
Well, Thomas wasn't just going to let that slide.
Now we have to wait and see if Thomas will take the chance and post more workout videos or if he has learned his lesson.