He has 18 holes left in which to hand his confidence a further boost by heading to Augusta National with a win. It may, though, now be a vain pursuit.
Should McIlroy indeed fall short by close of play at the Arnold Palmer Invitational, three successive bogeys from the 14th hole on Saturday will be the crucial points of reference.
The second dropped shot was the most galling, given the missed putt from inside 3ft which caused it, his ball having been diverted by a spoke mark. Not that the 16th was easier to take; on a par five playing at a Saturday scoring average of four, McIlroy took two more.
The world No1 was four under par for his round, minus 12 in total, and lying second before these unforeseen aberrations. He was later to sign for a 71, a nine-under-par in total, which while decent enough looked a tad bittersweet. He could still win here, but it will take a serious effort to do so.
“I’m disappointed with the way I finished but I played well for the most part. I need to get off to a fast start; maybe four under through five or five under through nine,” said McIlroy of his final-round plan.
McIlroy will not have things his own way on day four. Far from it. Morgan Hoffman, Henrik Stenson, Matt Every, Matt Jones, Kevin Na, Jason Kokrak and Sean O’Hair are among a tightly-packed leading group after 54 holes.
Stenson has been firing out warning signs with Augusta National in mind for a number of weeks now.
In this tournament, he should be regarded as the firm Sunday favourite; a terrific third round of 66, his second in a row, took Stenson to 16 under. He is the man to catch, a position that history tells us Stenson relishes.
With all due respect to McIlroy and Stenson et al, the most popular winner in the hearts and minds of Orlando locals would arrive from far lower down the world rankings. No219, to be precise.
Sam Saunders, a grandson of Palmer himself, retains a chance of producing a fairytale story after his third round of 67 moved him to eight under par.
The fact that he hails from Orlando and has played Bay Hill literally hundreds of times is a clear advantage this weekend. As, of course, is the inevitable level of advice bestowed by an illustrious grandfather.
“Some people think you are going to shoot 21 under par. That’s not going to happen here,” Saunders explained. “I still believe the winning score will be around 15 under par.
“So, yes, I have got to go out there and do something special – but the important thing is it’s not 100% out of reach, in my opinion.”
Kiradech Aphibarnrat, whose curious claim to fame relates to the changing of his name by his mother during his youth because of superstition, produced the round of the day.
The Thai player’s 65, which propelled him to 10 under on aggregate, included a front nine of just 30. Aphibarnrat dreams of playing full time on the PGA Tour before too long.
“I love the golf courses out here and I love the people,” he said. “I will try to come over here and play but it is not easy. This is the No1 tour in the world; everyone wants to get here.” A few more days like this would come in handy then.
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