Ko has made a flying start to the season, with victory at the Australian Open being followed a week later by a convincing four stroke win at her native NZ Open.
A runner-up finish at the HSBC Women???s Champions event extended her record to five consecutive top-seven finishes in 2015, with Ko looking to continue her impressive run of form in Arizona this week.
South Korea???s Inbee Park takes a week off after the World No 2 lost out to compatriot So Yeon Ryu at the World Ladies Championship, although over half of the world???s top 20 feature in a star-studded field.
Karrie Webb, a two-time champion at Wildfire GC, returns to defend her title having birdied six of her final round back nine to snatch a one shot win last year.
???It???s just one of those courses where you can get on a roll,??? Webb said. ???Barring a couple of rounds we???ve played here in the last four years, the conditions have been perfect.”
The Australian has been grouped this week alongside the tournament???s other two previous winners, Yani Tseng and world No 3 Stacy Lewis, while US Women???s Open champion Michelle Wie is also involved.
Wie has made a disappointing start to the season as she battled a sinus infection, but hopes to be back to full fitness soon.??
???The doctor said that I probably won???t be feeling 100 percent for the next couple of weeks,” Wie said. “I???m feeling a lot better thankfully, but it???s been tough. Just being sick in general, it???s never fun, so really right now my No. 1 priority is just getting my health back in order.?????