Mickelson was in control from the start last year. He fired a 10-under 60 in the opening round to take the lead. Mickelson had a putt for the sixth 59 in PGA Tour history, but it painfully lipped out.
He followed with rounds of 65 and 64 to set the tournament's 54-hole scoring mark. After a closing 67, Mickelson ended at 28-under 256, which tied the second-lowest score in a 72-hole PGA Tour event. The win was his third at this event.
If Mickelson is unable to play, the field will be headlined by former Masters champion Bubba Watson, Lee Westwood and last week's winner Scott Stallings. Harris English, the Sony Open champ, and Humana winner Patrick Reed are also scheduled to tee it up this week.
The TPC Scottsdale will be overflowing with fans again this week. Last year, the tournament tallied 525,821 fans, falling a little more than 12,500 fans shy of the tournament record.
The feature destination as always is the enclosed par-3 16th, which will have as many as 20,000 fans on the hole alone.
Golf Channel will have coverage Thursday and Friday, as well as early coverage on the weekend before handing off to CBS in the afternoon.
The PGA Tour shifts back to California for the next two events. First up is the AT&T Pebble Beach National Pro-Am, which Brandt Snedeker won by two strokes last year.
OMEGA DUBAI DESERT CLASSIC, Emirates Golf Club, Dubai, United Arab Emirates - The European Tour wraps up its desert swing this week with the Omega Dubai Desert Classic.
The event is celebrating it 25th anniversary and a who's who of former champions are in the field this week. World No. 1 Tiger Woods, a two-time winner, headlines that list.
Woods will be joined in the field by the likes of Fred Couples, Mark O'Meara, Ernie Els, Rory McIlroy, Colin Montgomerie, Jose Maria Olazabal and Javier Ballesteros, son of the late Seve Ballesteros.
There will be a champions challenge on Tuesday with the above players all competing.
Stephen Gallacher only needed two good rounds last year to earn the title. The Scotsman opened with a 9-under 63 and backed it up with a 10-under 62 in round three. With those two rounds alone, he would have tied for second place.
Gallacher went 3-under in the other two rounds to beat Richard Sterne by three shots. The win was Gallacher's second on the European Tour, and his winning total of 266 matched the tournament scoring record that Thomas Bjorn set in 2001.
Golf Channel will have early morning coverage of all four rounds.
The tour returns to South Africa next week for the Joburg Open, where Sterne cruised to a 7-stroke win last year.