Japanese sensation Hideki Matsuyama withdrew from the WGC-HSBC Champions Friday, citing a bad back.
Though the 2013-14 PGA Tour season is less than a month old, this marks the second time the 21-year-old has been forced to withdraw from an event. He left the field at the Shriners Hospitals for Children Open last month shortly before his opening-round tee time, citing illness.
Matsuyama carded two birdies against a lone bogey Thursday at Sheshan International Golf Club en route to a 1-under 71 that left him six shots off the pace through one round. He withdrew Friday before the start of his second round.
Now up to No. 28 in the latest world rankings, Matsuyama has had a successful year since turning professional in April. The 21-year-old has won three times on the Asian Tour and qualified for last month's Presidents Cup, in which he compiled a 1-3-1 individual record. He tied for third at the season-opening Frys.com Open, his best career PGA Tour finish to date, and tied for 25th last week at the CIMB Classic in Malaysia.