Romo holed the eagle on the seventh hole on Thursday at Trinity Forest Golf Club in Dallas. He ended the round with a 5-over-76, tying for 148th on the leaderboard. Romo is playing in the event on a sponsor's exemption.
Denny McCarthy topped the leaderboard with a first round of 63. Brooks Koepka is also in the hunt at 6-under-par.
Romo birdied hole No. 1 on Thursday. He made par on No. 2, No. 3 and No. 4, before carding a bogey on No. 5. Romo made par again on No. 6, before walking to the tee on No. 7.
He hit a 279-yard tee shot on the par-5, 544-yard hole. His next shot traveled 239 yards and landed just short of the green. Romo lined up his next shot with a wedge, while standing 21 yards from the hole. He chipped his third shot onto the green and watched it roll into the hole for an eagle. The shot made Romo 2-under-par at the time.
He made par on No. 8 before going even with a double bogey on No. 9. Romo made par on five holes on the back nine, but couldn't get a stroke back. He hit another double bogey on No. 13. He also carded bogeys on No. 14, No. 15 and No. 17, shooting a 40 down the stretch.
"A couple of those tee shots really cost me just because they're penal in those areas," Romo told reporters. "You can't miss them there. The separation between these guys is the ability to do it for long stretches, consistency. I think just a few tee shots cost me the round."
Romo will need a very low round on Friday to have a chance at making the cut for the weekend.