Mickelson so nearly broke 60 in last year's opening round, a putt at the last circling the hole before he signed for a round of 60 and proceeded to lead from go to whoa, eventually winning by four over Brandt Snedeker.
Mickelson comes off a runner-up finish in Abu Dhabi and the withdrawal at Torrey Pines and he has withdrawn from the Pro Am on Wednesday this week in order to work further on his back. He travelled to Georgia for help from a back specialist which has apparently assisted but there is a question mark over his chances.
Webb Simpson has recorded top tens at each of his last two starts in the event and had been in great form before an average week at the Humana Challenge. Six of his last eight rounds here have been in the sixties so his chances look rather good.
Ryan Moore finished 4th last year powering home over the weekend with consecutive rounds of 65. Moore has been pretty solid in limited starts of late and might be one for slightly longer odds.
Harris English was just average at the Humana Challenge but in earlier events on the PGA Tour he had been very good. He has made both cuts in this event without doing anything too spectacular but he is a much improved golfer of late.
Keegan Bradley is playing solidly without really contending of late and has a couple of respectable efforts to his name in this event. At some stage he will turn average into great in terms of recent finishes and if it was this week there would be little surprise.
Billy Horschel was 11th in his only start in the event in 2013 and he has played well enough of late to be a factor this week.
In his first event of 2014 Hideki Matsuyama finished 16th at last week's Farmers Insurance Open and the standout on last year's Japan Tour during his rookie season is such a good young prospect he could surprise this week. He played beautifully in PGA Tour events last year and now as a member he is expected to develop into a multiple winner.
Gary Woodland has done enough in this event to believe he could be a possible winner. He contended last week before finishing 10th and on top of several good tournaments he appears to be approaching winning form.
The Australians are headed by Marc Leishman and Matt Jones, Leishman finishing 5th and 2nd in his first two starts this year but the Victorian does not enjoy a good record here.
Despite the fact that he lives in the region Matt Jones does not enjoy a good record at the TPC of Scottsdale. He continues to play well on the PGA Tour but his lack of success at the venue is a concern.
Geoff Ogilvy, Robert Allenby, Aaron Baddeley, Greg Chalmers and Steve Bowditch are other Australians in the field.