American Steele almost had a hole-in-one and tamed testing winds to shoot a three-under-par 67 that could have been even better had he not found the water with his second shot for a closing bogey at the par-five 18th.
At five-under 135, he leads by one stroke from English duo Lee Westwood and Luke Donald and American J.T. Poston at PGA National in Palm Gardens.
Steele, a three-times PGA Tour winner, has made an excellent living without achieving any level of fame in his decade on the tour but he can match it with anyone on his day, and Friday was one of those days.
"I'm feeling really confident with my swing," Steele told PGA Tour Radio.
"I'm used to playing in a lot of wind so this feels pretty comfortable and I feel like my distance control is really nice."
Steele could only laugh at how close he came to an ace at the 180-yard 16th, where his tee shot hit the hole but somehow defied gravity and horseshoed out.
"It's hard to tell from the tee but it looked like it had a chance and then we saw it abruptly move, the way it would only do if it hit the hole," he said.
The near-miss cost Steele a car awarded to any ace, but that was probably not of huge concern to a guy whose career prizemoney exceeds $15 million.
Hot on Steele's heels, former world number one Westwood is feeling at home on a course that demands precision with water lurking around every turn.
"It's a good ball-strikers golf course," said the 46-year-old, a recent winner of the Abu Dhabi Open on the European Tour. "You've got to play from the fairway."
A more recent number one, Koepka, bowed out ignominiously after consecutive rounds of 74 that he blamed on a rusty short game, the result of having played a very limited schedule while rehabilitating a knee injury the past few months.
"Just need to pick it up a little bit, pick up the pace, maybe a little bit more touch around the greens, a little bit more feel but the way I'm striking it, I'm very pleased," said the four-times major champion.
(Reporting by Andrew Both in Cary, North Carolina; Editing by Stephen Coates)