CHENGDU, China (Reuters) - Defending champion Yang Yong-eun has pledged to become the first back-to-back winner of this month's China Open, event organizers said on Wednesday.

South Korea's Yang, who became the first Asian golfer to win one of the four majors at the 2009 PGA Championship, heads a quality field alongside Ireland's Padraig Harrington.

Harrington has won three majors but will be looking to break a three-year title drought on the European Tour at the $3 million co-sanctioned event with the OneAsia tour in Chengdu from April 21-24.

Yang, however, has no such concerns over his form after a solid top-20 finish at the U.S. Masters.

"I know the China Open title has never been successfully defended," the 39-year-old said. "But there is a first time for everything."

Also chasing a record purse will be Briton Colin Montgomerie, Europe's 2010 Ryder Cup captain, Spain's Sergio Garcia and Chinese number one Liang Wenchong.

Liang, the OneAsia tour's 2010 Order of Merit champion, will be making his seventh successive bid to become the third home player to win the event.

He will, however, be able to draw on a victory at the Luxehills International Country Club, where he triumphed at last year's Chengdu Open.

"I've been especially excited about (this event) ever since Luxehills was announced as the host venue," he said.

"I feel fresh, relaxed and on top of my game, but if I am to win against a world class field, I will have to play my very best."

Montgomerie said: "Having won both the Hong Kong Open and the Macau Open, I would love to make it a hat-trick (in the region)."

(Reporting by Alastair Himmer in Tokyo; Editing by John O'Brien)