Spain's second-ranked Jon Rahm can overtake Rory McIlroy and become world number one for the first time with a victory at this week's US PGA Workday Charity Open.

The 25-year-old Spaniard tees off Thursday alongside reigning US Open champion Gary Woodland and Norway's Viktor Hovland at Muirfield Village in Thursday's opening round.

Four-time major champion McIlroy of Northern Ireland has topped the rankings since February, just before the start of a three-month hiatus due to the global coronavirus pandemic.

But with McIlroy idle this week ahead of next week's Memorial tournament over the same mid-Ohio layout, Rahm has a chance to swipe the top spot with a victory in the new event, created to fill a gap in the schedule after the John Deere Classic was called off due to Covid-19 issues.

The only Spaniard to hold the world number one ranking was the late Seve Ballesteros, who was there for 61 weeks, exchanging the spot with Australian Greg Norman from 1986-1989.

Rahm credits his willingness to fight for every shot as a reason his results have been consistent enough to give him a chance to reach the top.

"I fight on the golf course for every shot I hit every single day," Rahm said Wednesday. "That never give up attitude, even if I'm starting 30th in the final round and I've got no chance of winning, I still want to finish as high as possible.

"It's important to fight for those shots. Top 10s are still top 10s. And the better you play, the more chances you are in the top 10, the more chances you will have to win."

The Workday will be the fifth event in a row played without spectators, who were to have returned to the PGA at next week's Jack Nicklaus-hosted event before spiking coronavirus cases in the area forced officials to scrap that plan.

Rahm was charging earlier in the 2019-20 season, winning last October's Spanish Open and the World Tour championship at Dubai in November, taking Race to Dubai and European Tour Player of the Year honors.

He was a runner-up at Torrey Pines in January and third at the WGC Mexico Championship just before the shutdown.

Since returning from the layoff, Rahm has a missed cut and shares of 33rd and 37th.

"I don't want to be a player who gets maybe a couple wins and everything else is missed cuts or T40s because that's not who I am," Rahm said.

"Every time I tee it up I fight my hardest on every shot. That's why that grind kind of translates to consistent play."

Eighth-ranked Patrick Cantlay, the defending Memorial champion, is among seven of the world's top 15 at the event, including three of the top five with Rahm, fourth-ranked Justin Thomas and number five Brooks Koepka, who withdrew two weeks ago at the Travelers Championship after his caddie tested positive for Covid-19.

Koepka and Thomas will join Australian Jason Day for the first two rounds, while Cantlay plays alongside US compatriots Jordan Spieth and Phil Mickelson.

Americans Denny McCarthy and Nick Watney and South African Dylan Frittelli, who previously tested positive for COVID-19, have been cleared to return and will play this week.