Questionable decisions. And a match play performance that suggested he'd be getting an earlier start on Masters preparation.
Woods then scrambled his way to pars at the 14th and 15th before McIlory appeared to continue his momentum with a 395-yard drive at the 16th, with the American in the bunker.
Dane Lucas Bjerregaard pulled off a stunning victory over idol Tiger Woods in the quarter-finals of the WGC-Dell Technologies Match Play in Texas on Saturday. The winners will advance to the semifinals on Sunday morning before the finals take place later in the day.
McIlroy needs no reminding the last occasion he and Woods were grouped in a regular tournament was the Sunday prior to last year's Ryder Cup when Woods ended a five-year victory absence to capture the Tour Championship in Atlanta. It's exciting for the tournament. I am, too, 100 per cent of the time - except for today. "He's such a class individual and a player to the point where you nearly feel sorry for doing that to him over the last few holes". I've continued to do that this week.
"I've heard all sorts of things, especially this afternoon, where I think they've had a few (beers)".
Woods and McIlroy are very familiar with one another.
Earlier, Woods sealed a two-and-one victory over Rory McIlroy in their first match play meeting.
That finish came after Spieth had to win two of the final three holes Wednesday to tie his opening match with Billy Horschel.
"I've heard, "Beer Garden" and seen people lifting their beer up in the air and saying, "This is you, man", Bjerregaard said. "It was a tough day all around and I'm happy to advance".
"He played well in tough conditions", Woods said.
"We read it inside left, left center, and the putt went left", he said.
"I don't know right now (about Masters preparation)". I didn't put up much of a fight at the Tour Championship but hopefully it will be better this time'. "And it was a bit of a bonus".
Woods had not made it this far in the tournament since 2008, the last of his three victories.
He eagled the 16th hole to tie, then birdied 17 to remain level and watched Woods miss a putt on the last to end it.
But Cantlay would not win another hole, making a big mistake by driving into a penalty area at the downhill ninth.
"It's always nice to beat the number one player in the world", said Grace, who can do no worse than a playoff with Johnson - who must beat Japan's Hideki Matsuyama and have Grace lose to American Chez Reavie to force it. "You've got to give me a little time to calm down". "It was just one of those weird spots".
Yet Woods never would close the door, leaving it open for Bjerregaard to come back and on the 16th green, with Bjerregaard's ball just inside Woods', the unthinkable happened.
Na, who had upset English second seed Justin Rose 2-up, began with a birdie but dropped the next six holes and never recovered.
"It was big for us inside the ropes too", Woods said.
Italy's Francesco Molinari, the highest remaining seed at seventh, will meet USA 48th seed Kevin Kisner, last year's runner-up to Bubba Watson, in Sunday's other morning semi-final to set up an 18-hole afternoon championship final.
Woods said he never paid attention to the other match until his was almost over because "I needed to take care of my own match".