(Reuters) - Exciting Japanese talent Hideki Matsuyama withdrew from the second event of the PGA Tour's 2013-14 season on Thursday, due to an unspecified illness, organisers said.
Matsuyama pulled out before teeing off in the opening round of the Shriners Hospitals for Children Open in Las Vegas and was replaced in the field by American Jim Herman.
The 21-year-old Japanese, ranked 29th in the world, had been one of the biggest drawcards for the event, having tied for third at last week's Frys.com Open on his debut as a tour member.
In a total of seven career starts on the U.S. circuit, the richly talented Matsuyama has yet to finish worse than joint 21st.
He won the Asian Amateur title in 2010 and 2011 to qualify for the Masters the following years and made the cut at Augusta National on both occasions.
Matsuyama turned professional in April and proved he can compete with the game's elite, recording top-10s at the U.S. Open and British Open. He made an impressive debut at the Presidents Cup for the Internationals earlier this month.
Matsuyama is a four-time winner on his home tour and many pundits expect him to enjoy a more successful career than his celebrated compatriot Ryo Ishikawa, who is playing in Las Vegas this week.
American world number 11 Zach Johnson and 24th-ranked compatriot Webb Simpson head the field for the Shriners Hospitals for Children Open.
(Reporting by Mark Lamport-Stokes in Los Angeles; Editing by Julian Linden)