Rory McIlroy backed up his pre-tournament prediction in brilliant fashion with a flawless 65 as Open champion.
Phil Mickelson suffered an astonishing collapse in the first round of the WGC-HSBC Champions on Thursday.
Without a win all season, McIlroy is a lowly 62nd on the European Tour's Race to Dubai and needs to move into the top 60 this week to have a chance of qualifying for the DP World Tour Championship in November.
The 24-year-old insisted he was more likely to win in Shanghai than miss out on a trip to Dubai and was as good as his word at Sheshan International Golf Club, carding eight birdies and just one bogey to finish seven under par.
That gave the Northern Irishman a two-shot lead over Spain's Gonzalo Fernandez-Castano, who won the BMW Masters across the city at Lake Malaren on Sunday, and Welshman Jamie Donaldson, who both shot 67. US Open champion Justin Rose, Bubba Watson, Jordan Spieth and Tommy Fleetwood are a shot further back on four under.
Mickelson had briefly shared the lead with McIlroy when he picked up his sixth birdie of the day on the seventh - having started from the 10th - but ran up a quadruple-bogey nine on the eighth.
After seeing his third shot come up short of the flag and roll down a bank into water guarding the green, Mickelson took a penalty drop and then span his fifth shot from the drop zone back into the same hazard.
The left-hander finally found the putting surface with his seventh shot and two-putted, but compounded his misery by hitting his approach to the ninth into the water to the right of the green.
That led to a bogey five and meant Mickelson had to settle for an opening 71, one under par.
McIlroy won five times in 2012, including a second major title by eight shots, to finish top of the money lists on both side of the Atlantic, but his only 'win' this season came in an 18-hole exhibition match against Tiger Woods on Monday.
Woods said afterwards that he felt McIlroy would claim a victory before the end of the year and the Northern Irishman quickly set about proving his Nike stablemate correct, starting from the 10th with a birdie.
A bogey on the 11th would prove to be the only dropped shot of the day, McIlroy carding further birdies on the 12th, 14th, 16th and 18th to be out in 32 and picking up shots on the first and second to move into the lead.
As soon as Mickelson drew level McIlroy responded with another birdie on the eighth, the hole Mickelson would make such a mess of in the group behind.
McIlroy is less than 4,000 euros (£3,400) behind Garth Mulroy in 60th place on the money list, but will now have his eyes firmly on the first prize of just over one million euros (£856,000).