Rory McIlroy hits a shot during the Zozo Championship on Sunday in Inzai, Japan. Photo: VCG

World No.2 Rory McIlroy said his strongest season in years has motivated him to recapture golf's top ranking, as he leads a field packed with Major winners into this week's WGC-HSBC Champions in Shanghai.

Asia's biggest event tees off Thursday without world No.1 Brooks Koepka, out with a knee strain, nor a rejuvenated Tiger Woods, who electrified golf with a record-tying 82nd PGA Tour win in Japan on Monday.

But an event dubbed "Asia's Major" still features plenty of star power including 15 past Major champions such as Justin Rose, Bubba Watson, Sergio Garcia, Phil Mickelson, Jordan Spieth, Patrick Reed and Adam Scott.

But few are playing as well as McIlroy, the 2019 FedEx Cup champion and PGA Tour Player of the Year, who won the Tour Championship event in August and tied for third behind Woods at the Zozo Championship in Japan on Monday.

The 30-year-old Northern Irishman's stellar season has propelled him up the world golf rankings, and although a victory in Shanghai won't push him past the absent Koepka, McIlroy said he's not finished.

"I want to get as many world ranking points as I possibly can and try to close that gap on No.1," he said at Sheshan International Golf Club. "So you know, pretty motivated coming into the week." 

That motivation might have been juiced by Koepka, who this month dismissed the notion of a burgeoning rivalry with McIlroy by pointing out that the Northern Irishman hadn't won a Major in five years.

McIlroy, who last sat on golf's pinnacle four years ago, subsequently played down the comments, saying that Koepka had a point, and that the two were "good friends."

The Northern Irishman had staked his claim to be among the world's best with four Majors before the age of 25, until younger stars eclipsed him.

"But if I play well the next few weeks, you know, I'll have a great platform going into next year. I've achieved most things that I've wanted to this year," he said in Shanghai.

"I'm happy with where everything is, and yeah, just want to finish the year off strongly because I feel the year that I've had deserves a finish like that."

The $10.25 million Shanghai event, with a winner's prize of $1.7 million, is the third and final leg of the PGA Tour's Asian swing, after the Zozo Championship and the CJ Cup in South Korea the week before.

In Japan, McIlroy led the field in par-five scoring, which should serve him well on the lengthy Sheshan course, widely considered one of the toughest on the Tour.