"I think I'm a bit of a pest on the golf course," Day said in his pre-tournament press conference at Austin Country Club in Austin when asked why he's been much a formidable opponent at the match play event.
"I'm one of those guys that just - I think the biggest example is I played Rory two years ago and he hit it so much better than me. I mean he should have won. But my short game - I just knew, I said I'm just going to wear him out with my short game. I was hitting it everywhere. I wasn't hitting greens.
"I was clearly not hitting it as good and not as pretty as him. And I just said, you know what, it doesn't matter how it's going to happen, I'm just going to wear him out with my short game and annoy him.
Day will start as one of the favourites this week given his track record at the event and also because his form in early 2018 suggests he is approaching the form that has seen his rise to World No. 1 in the past.
“I always say this is the easiest and hardest tournament to win because there are seven rounds, seven guys that’s all you have to beat,” said Day.
“You’re not playing against the entire field. If you can get past those seven guys and play some good golf and kind of hit that peak coming into this event then you can walk away with the W.
“On the other hand, the competition is tough and getting higher and higher every year. With that being said, I am looking forward to a tough week mentally and physically and am going to grind it out the best I can.”
"It (his game) definitely feels good. I enjoy match play. I had some good form coming into this week. Obviously the T-22nd, I felt like I played a lot better than that. So it was something that I can build on, take all the good stuff from what happened last week to this week. And if I can do that, I've had good success here.
"I've got some tough competitors. I think everyone has tough competitors this week, because it doesn't matter who the favorite is. It's not like a tennis, per se, normally the high ranked seeds get through to the finals. But golf is a little bit of a different beast when it comes to that."
Day heads up Group 8 in the 16-group round robin matches. Also in Day’s group are Jason Dufner, James Hahn and the man he beat in the 2016 final, Louis Oosthuizen, though Day’s current form is expected to get him through to the Round of 16 on Saturday morning.
Day’s fellow countrymen Marc Leishman and Cameron Smith complete the Australian contingent.
Leishman has twice made the Round of 16 in just four starts in the event and has three top tens in eight starts this season including a 7th last week at Bay Hill.
Leishman heads a group which includes Branden Grace, Julian Suri and a resurgent Bubba Watson.
Smith gets to play the WGC-Dell Match Play for the first occasion but his career includes a win at the Australian Amateur Championship and so match play is not new to him. He missed the cut at Bay Hill but his form for most of the season has been very solid.
Smith’s group includes Hideki Matsuyama, Patrick Cantlay and Yusaku Miyazato.
The tournament’s natural favourites are the defending champion Dustin Johnson, last year’s runner-up John Rahm and Rory McIlroy but there is every reason to believe that Australia’s significant record in the event which includes four wins and one runner-up finish can be extended.
DAVID NORTHEY - PUTTING FROM OFF THE GREEN
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