Hossler was also bogey-free on the Pebble Beach course, although he had a near miss at the 18th after he was forced to make an eight-foot putt for par, following a wayward tee shot. Par: 72); Monterey Peninsula (Yardage: 6,958.
It matches his outlook on the year.
Gerry McIlroy was wearing a Seminole sweater and has spent a good amount of time this winter at the South Florida club practicing.
"I feel like there's nothing in my way", McIlroy said.
McIlroy has moved up three spots to No. 8 in the world since the beginning of the year thanks to a tie for third at the Abu Dhabi HSBC Championship and a second-place finish at the Dubai Desert Classic. Playing at Pebble Beach for the 22nd time, Mickelson has won the tournament four times. The Dunhill arguably gets a nod with the golf courses - St. Andrews and Carnoustie, along with Kingsbarns.
It is the first time McIlroy has entered the Pebble Beach Pro-Am, and he is partnered with his father.
'I will have played a lot of tournament golf leading up to it.
"What goes through my head is I still believe that most of the guys that sit on this stage right here, you ask them who do they want putting on your team in a Ryder Cup, and I believe they would say my name - so I have no doubt in my abilities", Spieth said. "But with how I was sort of dejected and wanting to get away from it I was then, to how rejuvenated and optimistic I am now, it feels a lot different that way".
If McIlroy needed a shot of confidence, Day was happy to provide it.
The Pebble Beach Pro-Am stretches the coast of California and runs through Monterrey Peninsula Country Club, Spyglass Hill and historic Pebble Beach throughout the week. Dunne is an avid golfer and said to be among a very few who claim memberships at Augusta National, Pine Valley, Cypress Point and Seminole. No need for introductions.
Former world No.1 Day mixed five birdies with two bogeys to leave himself four shots off American leaders Kevin Streelman (65, Spyglass) and Beau Hossler (65, Pebble Beach) at seven under.