Patience. Aggression. Extend the lead. If you're not on your game, post a good score.
That carried Day to a 2-under 70 in rough weather Saturday at the Arnold Palmer Invitational, which gave him a 2-shot lead and one more day to show he's a quick study. He has won the past three times he had a share of the 54-hole lead.
"It's a different pressure, but it's a good, uncomfortable feeling that I've always talked about, that I always want in my career," Day said. "Because I know that if I've got that, I have a comfortable feeling that I'm doing it right. And usually, I'm around the lead."
It wasn't easy Saturday, even though tee times were moved forward because of a forecast of storms in the afternoon. That didn't keep the rain from showing up, occasionally heavily, or for the temperatures to fluctuate and the wind to swirl.
"I felt like I couldn't get any momentum, especially with the umbrella up and down, the rain gear on and off," Day said. "All that said, I feel like I stayed patient to ground out a 2-under par."
Day finished at 15-under 201, two shots clear of Stenson (70), Merritt (67) and Chappell (67). It was a grind for everyone.
Stenson wasted little time in cutting into the deficit when he two-putted for birdie on the par-5 fourth, hit a wedge to 6 feet for birdie on the next hole and then took the lead with a 10-foot eagle putt on the par-5 sixth.
But the hole after that was the start of some frustrations. Stenson found a plugged lie in the bunker, didn't try anything fancy and accepted a bogey. He caught two other buried lies in the sand, one of which cost him momentum. His tee shot narrowly missed clearing the bunker on the par-5 12th and plugged under the lip. Stenson could only hit wedge to get out and made a bogey. That cost him a share of the lead, and he never caught up.
Even so, he is a threat at Bay Hill. Stenson is now 51-under in his past 17 rounds -- 16 of those under par -- and had a chance to win last year until a pair of three-putts (for bogey and for par) late in his round.
"Hopefully, we're in a different position now," Stenson said. "We need to come from behind and play a really good round tomorrow if we want to have a shot at it."
Day will be in the final group with Merritt, who logged his first PGA Tour victory by three shots over Rickie Fowler last year at the Quicken Loans National. Stenson will be in the penultimate group with Chappell, who is playing his 150th PGA Tour event and still trying to win.
Chappell got sick on Thursday and hasn't quite recovered, which, in a way, might have helped. With limited energy, he has been trying to keep it simple, and so far, that has worked out nicely. Chappell was two shots behind going into the final round at Riviera, which he knew well from his days at UCLA, and he closed with a 76. He played in the final group at Sea Island last year, three shots behind, and was runner-up to Kevin Kisner.
Adam Scott, coming off back-to-back victories on the Florida swing, was trying to give himself a chance when he was 9 under on the 18th. Instead, he went into the water with his second shot, made triple-bogey and posted a 70 to fall nine shots behind.
Rory McIlroy doesn't have much at stake, either. Whatever momentum he was trying to find ended with an approach into the water on the 18th (his ninth hole), and he made two more double-bogeys on his way to a 75. He was 16 shots behind.
Day would love to get back to No. 1 in the world. A victory Sunday would at least get him within range of Jordan Spieth with the Masters approaching.
"It's good to be back in contention," Day said. "I love the feeling of being in the lead. Now I have to push forward until Sunday is done. If I can scratch out a win tomorrow, it's going to do a lot of wonders for my confidence, knowing that if I've held the lead every single day, won wire-to-wire, it's perfect timing with what's coming around the corner. And we're talking about Augusta."
The last wire-to-wire winner at Bay Hill (no ties) was Fred Couples in 1992.