Ernie Els, who won the tournament by 13 strokes two years ago, was five shots off the pace at 1-under-par 71.
Els is chasing his first win of the year after finishing second Monday in the PGA TOUR's Verizon Heritage -- his third top-three finish of the year.
'I played good enough,' said Els, who three-putted the 10th and 11th for bogeys after misjudging the greens. 'I just didn't want to shoot myself out of it. I had some chances, I could have been three under easily.'
Jacquelin, who let his second round lead slip away at last weeks China Open, picked up seven birdies against just one bogey.
'I'm doing pretty well at the moment,' said Jacquelin, runner up at last month's Estoril Open de Portugal.
'It's always good to shoot low in the first round and relax a bit and take the pressure off me,' he said. 'I'm going to play exactly the same tomorrow and take the same feelings that I've had over the last month and we'll see.'
Denmark's Soren Kjeldsen was one stroke off the pace after shooting a 5-under 67, while Lee Sung of South Korea, Gregory Havret of France, and Australia's Gavin Flint had rounds of 68.
Flint's round included an eagle three on the par-5 second hole, one of just two eagles for the day at the Tomson Shanghai Pudong Golf Club's reconfigured 7,326-yard course.
Defending champion Gonzalo Fernandez-Castano was at 1-over 73, while fellow Spaniard and 2004 winner Miguel-Angel Jimenez had a 70. Sunday's China Open winner Markus Brier of Austria shot a solid 1-under-par 71.
The Open is co-sanctioned by the European and Asian Tours.