What mattered was being free of the pressure of the U.S. tour, where he has struggled to find his niche.
Instead, Stadler led two-time Masters champion Phil Mickelson by one shot, carding a 3-under 69 on Friday for an 11-under 133 total to top a field that includes 10 of the world's top 20.
Drawing the largest galleries in the absence of Tiger Woods, No. 2-ranked Mickelson shot a 66 with four birdies on the last five holes to go with Thursday's 68. Englishman Ross Fisher (68) and Simon Yates (66) of Scotland were three behind at the Sheshan Golf Club.
Vijay Singh trailed by four after a 70 with other high-profile players far off the pace in the $5 million event, the biggest purse in Asian golf.
'I just kind of came here to have fun,' said Stadler, who saved his U.S. Tour card on Sunday -- the final day of the season.
He needed to finish in the top 125 on the money list, and ended up at No. 124.
'I came here to enjoy the whole experience, not really, not really taking it all that seriously,' he said, pausing to rephrase his reply. 'That doesn't sound right. I don't know how to word this properly. More relaxed.'
So far, Stadler seems comfortable everywhere except the U.S. tour. He's had two strong seasons on the Nationwide Tour -- the level just below the U.S. tour -- and his biggest win came in 2006 in Australia.
'I'm definitely more comfortable now that I am over there (U.S. tour),' he said. 'I don't know why that is. I do enjoy myself when I'm out of the country. I don't know what the reason is for that, but I definitely feel more at ease when I'm playing over here.'
The son of 1982 Masters champion Craig Stadler, the younger Stadler said the famous name did not bring extra pressure. However, it might raise the expectations of others. And that, in turn, my cause him to press.
'I think I have expected too much out of myself on tour and I think I probably put a little more pressure on myself than I should,' he said. Though the pressure is off Stadler in China, he said the field in the HSBC Champions -- the first event of the 2008 European Tour season -- was as good as any in the United States.
'The competition over here is phenomenal,' Stadler said. 'This field here is every bit as good as it is every week in the States. It's definitely got nothing to do with that. I don't know how to pinpoint it.'
Mickelson finally produced on his first Asia swing. Last week he finished 16 behind in the Singapore Open. On Friday, he birdied four of the last five holes, negotiating a difficult wind and thick Bermuda rough that made the 7,199-yard course more testing than it was in a light breeze and sunshine on Thursday.
Mickelson ran in a 3-foot birdie putt on No. 14, dropped another from 10 feet at 16. On a roll, he birdied from 25 feet on 17 and had a 4-footer on 18.
'I played solid throughout and didn't make a bogey,' Mickelson said. 'I was able to play a good round in some tough conditions starting out, although the wind died down in the end.
'I like the golf course a lot,' Mickelson added. 'It's very similar to what we see on tour in the U.S. The greens are putting beautifully. ... If you read them well you are going to make a lot of putts.'
Unlike Mickelson, many of the world's other top-ranked players struggled on Friday.
British Open champion Padraig Harrington and U.S. Open winner Angel Cabrera each shot 72. So did Sergio Garcia.
Two-time U.S. Open champion Retief Goosen shot 74, Ernie Els had a 75, and Colin Montgomerie slipped to 78. Also, Niclas Fasth, who shared the first-round lead with Stadler, shot a 75 and was tied to drop into a tie for seventh at 5 under.