Malaysia's Ben Leong carded a six under par score of 66 in the opening round of the 28th Volvo China Open in Shenzhen on Thursday to lead the field of 143 players by one shot.

The 37-year-old posted even nines of three under par 33 for his impressive bogey-free round over the 7,145-yard Neil Haworth-designed golf course at Hidden Grace Golf Club in Shenzhen.

Leong, who has 14 professional wins to his credit, had just 28 putts in his impressive round, which started on the 10th tee at 11:40 am.

"I struck the ball really well today," said Leong. "The drives are pretty demanding here, but I drove the ball pretty well all day.

"It's a good golf course and is in great shape. I've been playing quite well recently, but I got sick in Macao and had to withdraw from that event. I holed a putt of around 40 feet on the last hole to save par, so my dinner will taste all the better for that tonight."

Australia's Jack Thompson had just 27 putts in his five under par round of 67, which included an incredible nine birdies.

At five under par Thompson sits alongside Thai players Chonlatit Chuenboonngam and Settee Prakonvech, Spain's Eugenio Chacarra and home players Li Linqiang, and not surprisingly, former champion Zhang Huilin.

Li gave himself the perfect 20th birthday gift on Thursday with his impressive round of 67, all the more so since this was his first ever round at Hidden Grace Golf Club.

"My target was an even par round today, particularly as I have not played the golf course before," said Li, who is based in Haikou city and is already a winner on the China Tour.

"My putting was very good today – I had only 28 putts and I holed a couple of long ones for par. I'll try to keep playing the same way tomorrow as I think my strategy is working quite well.

"I don't think I am at my best right now as I have had an injury on my left wrist for a couple of months, but it doesn't affect my swing. It just feels painful.

"I don't have a plan to go out and celebrate my birthday tonight. This is my first time to play in the Volvo China Open, and so I want to do my best."

Former champion Zhang worked his way up the leaderboard to also post a five under par 67 with six birdies and a solitary bogey on the long par four fifth hole, which played the hardest of all 18 holes today.

"Overall I'm satisfied with my round today," said Zhang, the champion here in 2020. "My putting was good all day, and then I chipped in for birdie on the par four 15th hole, which was the second-hardest hole on the golf course today."

"I want to thank the fans who came out and cheered me on today. I don't feel any pressure when I'm playing in front of them. I'm not thinking too much about winning. When you say you're playing well it often doesn't work out well," he added.

Pre-tournament favorite Andy Ogletree went out in three under par 33 but after making a birdie on the par four 10th hole he then had eight straight pars to finish at four under par 68, but only two off the lead.

Hitting only eight out of 14 fairways and then 12 out of 18 greens in regulation, Ogletree was saved by his putter, as he needed only 26 putts to complete the round.

Former Ryder Cup player Graeme McDowell struggled to an even par round of 72, and in joint 61st place he will need to significantly improve on that if he is to compete on the weekend in this $1.5 million event, which is co-sanctioned by the China Tour and the Asian Tour.

The 44-year-old Northern Irishman did not take advantage of the par five holes at Hidden Grace Golf Club making a double bogey seven on the ninth hole and then a bogey six on the 13th, which played the easiest hole on the golf course today.

Play was suspended due to poor light at 6:01 pm and 16 groups will return to the course early tomorrow to complete their opening rounds.