After beginning the day one behind the surprise leader, Peter Malnati, Day finally got his round heading in the right direction when he hit a brilliant approach from the left hand rough to a foot at the 9th beginning a run of five birdies in his next seven holes that would sweep him to the lead.
"I knew it wasn't going to be like this forever," said Day referring to his slow start. "I knew that things were going to turn around and that when I was out of position save myself a par and keep patient and the birdies will come.
"Tomorrow is going to be challenging. There are a lot of good players trying to win for the first or second time this season and they will be able to get out there with a little less pressure and post a score. I have all the pressure on my shoulders but I would much rather be in this position than chasing"
Day leads by two over Nick Watney who appears to be once again producing the sort of form that has seen him win six PGA Tour titles, the last of which came more than five years ago however.
Watney reeled of a third round of 66, recovering from a double bogey at the 11th today with four birdies in his last six holes to move within two of Day with whom he will play tomorrow..
The shot that started a run of five birdies in seven holes for Day - his approach to the 9th.
A win for Day tomorrow would move him to 8th in the World Ranking from his current 14th position which, interestingly, is his worst ranking since November of 2013.
Day would also reveal that he and wife Ellie are expecting their third child in November and so a win tomorrow would be yet another reason for celebration
Bryson De Chambeau, Peter Uihlein, Paul Casey and Aaron Wise are at 7 under par and three from Day's lead, Uihlein's round of 62 the best of the day by two shots over Phil Mickelson's 64.
Greg Chalmers is in 25th position while Adam Scott made the 36 hole cut but was not able to advance to Sunday play after his round of 72 left him amongst those restricted due to field size numbers.
Tiger Woods improved with a round of 68 to be in a share of 31st position.
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