LAKE FOREST, Ill. -- It happened without any warning, without any tangible notice. That's how these things work, though. One day you're shooting 61, the next day you're shooting 63, then -- bam! -- out of nowhere, you shoot "only" 69 and lead the tournament by "only" 6 strokes.
Alright, so maybe that's only if you are Jason Day, but he witnessed a palpable change in theme during Saturday's third round of the BMW Championship. Even though he actually extended his lead, no longer did Day look invincible. He posted four bogeys. He hit a ball out of bounds. He didn't make the game look as easy as he did during the first two days.
The guy who'd been in the zone for the opening 36 holes finally zoned out.
For one day, anyway.
On Thursday, after playing 17 holes in 10-under par and fresh off winning three of his past five starts, Day was asked to describe the curious nature of being in the zone.
"I'm not really -- it's almost like you're, I don't know, it's hard to -- I'm trying to vision in my head or explain it in a way that it's, I mean, it is what it is, I'm just going out there trying to ..." he attempted to explain before shaking his head with a laugh. "You asked me this bloody question; I can't answer it."
One day later, after polishing off that opening-round 61, then posting an eagle and seven birdies in a second-round 63, it was still a pertinent question.
So he was asked again.
And he still didn't have much of an explanation.
"I mean, I don't know -- I couldn't even tell you what the zone feels like, because I'm out there just ..." he offered.
"The zone? Something that you're not really thinking about mistakes, you're thinking about pushing forward, you're thinking about things that happen or things that could possibly happen, you kind of wash it out of your head."
Well, that certainly cleared things up.
Day can be excused, of course, for not being able to articulate his feelings on being in the zone. That might be the very definition of it, paralyzed to the idea that he wouldn't ever hit the best possible shot under every circumstance.
When he emerged from the zone on Saturday, though, posting six birdies against those four bogeys, he was well aware.
"I felt like my mind was clouded," he explained. "It was a little clouded today, so I'm hoping that it's a lot more free tomorrow and I can just kind of think to myself and really kind of just push forward and not really worry about who's around me like I did today, and that's kind of how it happened. I just was looking at other people instead of just kind of focusing on myself."
As he said these words, he quickly reminded himself that falling out of the zone didn't exactly crush his chances of winning.
"To shoot 69 even though I was doing that stuff is great, so I've just got to get back into my own little mind and go out and play golf."
Day is now on the verge of history -- no matter what.
If he wins, it will be his fifth PGA Tour victory of the season and fourth in his past six starts. He'll own the FedEx Cup points lead entering the season-ending Tour Championship and should at least creep into the Player of the Year conversation, one previously believed to be centered around only Jordan Spieth's name.
If Day doesn't win, he will join an ignominious list of six other players who have lost 6-shot 54-hole leads -- the largest advantage ever to eventually lose in the next round.
When faced with that proposition, he didn't hesitate. He just smiled and spoke the truth.
"To have a 6-shot lead and to lose," he offered, "would definitely suck."
Don't count on that happening. Day might have fallen out of the zone he was in during the tournament's first two rounds, but as we've witnessed from him lately, he doesn't need to be in that zone to still win.