LOUISVILLE, Ky. (AP) -- This has been a frustrating year for Jason Day.
The PGA Championship is changing his outlook.
After withdrawing last week at Firestone because of vertigo, Day shot a 6-under 65 on Friday that matched the best round of the PGA Championship and left him one stroke behind Rory McIlroy.
Given some of the problems the 26-year-old Australian has endured, he wasn't expecting to go that low.
''I'm a little surprised that it's kind of turned around so quick,'' Day said.
Day initially injured his left thumb while winning the Match Play Championship in February, and the persistent pain forced him to cut back his schedule. He played sparingly through the spring and summer, also developing a nasty hook that forced him to put in extra time on the practice range. He missed the cut at the Quicken Loans Nationals, tied for 58th at the British Open, and had to drop out at Firestone because of equilibrium problem.
His doctor determined the vertigo was caused by medication he was taking for his thumb and a persistent throat condition. After resting up for a couple of days, the problem faded away and he was able to take part in the final major of the year.
Now, Day is right in the mix for his first major title heading to the weekend, playing in the final group Saturday with McIlroy after posting a 36-hole total of 8-under 134.
''I'm excited,'' Day said. ''You can't not be excited to be in or around the lead in a major championship. Obviously, they are the hardest tournaments to win. But I'm looking forward to it.''
Despite his youth, this is hardly new territory. Day was runner-up at the 2011 Masters, and he's a two-time runner-up at the U.S. Open. Overall, he has seven top-10 finishes in the majors.
''I've been close a lot of times,'' he said. ''I just have to keep knocking on the door and hopefully it will fall my way one day. It either hopefully falls my way, or I just knock the door down and take it.''
Day knows it won't be easy to take, not with the guy he's chasing. McIlroy is a four-time major champion and has won his last two tournaments - romping to a wire-to-wire victory at the British Open, before rallying to win at Firestone. Over his last 10 rounds, McIlroy is 41-under par.
''I'm clearly not the favorite,'' Day said. ''This whole year, he's been playing great. He looks confident. He's hitting the ball longer and straighter than pretty much everyone in the field. It's going to be tough to beat him.''
Day was asked what he's learned from all those near misses.
''Just not to be scared about winning,'' he replied. ''It's OK to feel uncomfortable. ... I've just got to go out there and just embrace being uncomfortable.''
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