Billy Horschel will miss the WGC-HSBC Champions due to a back injury.
The American tweaked his back last Friday just before he left for China, but boarded the plane anyway in the hope that it would heal.
Unfortunately, the 2014 FedEx Cup winner discovered during a practice round on Tuesday at the Sheshan International course that his back had not healed.
The Florida native was forced to withdraw from the competition just two days before tee-off.
Joining the 78-man field in place of Horschel is Cameron Smith of Australia.
The Dutchman finished third and second in the first two weeks of the home-based competition.
NFL stars Tom Brady and Peyton Manning will also be involved.
The US President was among the viewers watching the TaylorMade Driving Relief.
The US President phoned in as McIlroy played in a Sunday fundraiser for coronavirus victims.
Syme donated his prize money to charity.
‘This is the life of a caddie…’
The Northern Irishman is ranked number one in the world.
Players entering the United States will face a 14-day quarantine period, while a strict testing regime will be in place at each tournament.
The experienced duo will be involved at Whistling Straits.
The world number 98 intends to split the 10,000 euros prize money between his own charity and a hospital in his native Rotterdam.