South Africa's James Kingston claimed the clubhouse lead in the weather-disrupted BMW PGA Championship as Luke Donald's bid for a third straight victory suffered a potentially fatal blow.
Kingston recorded seven birdies and one bogey to card a six-under-par 66 at Wentworth shortly before the threat of lightning saw play suspended at 3:42pm, with the final group having teed off seconds earlier.
A 90-minute delay meant the opening round would not be completed on schedule, but there was enough time for Donald to sign for an opening 78 to lie 12 shots off the lead.
"I got off to a very slow start, it felt like I had no rhythm and feel," said Donald, who is looking to emulate Colin Montgomerie (1998-2000) in winning the European Tour's flagship event for three years in succession.
"I don't know if it was the cold but I was struggling to feel my hands a little bit. Even when I had my opportunities I didn't take them."
Asked if his chances of victory had gone, Donald added: "You never say that. This place always plays quite tough. The forecast tomorrow is not good so hopefully a low round will get me back in the tournament, but it's certainly disappointing to be this far back."
Kingston is only in the field on a sponsor's invite after losing his card at the end of last season, but the 47-year-old made the most of it to lead by one shot from Finland's Mikko Ilonen, with Scotland's Scott Henry and Spain's Gonzalo Fernandez-Castano a shot further back.
"I never felt like I played poorly enough to lose my card and that's what makes it even more frustrating," said Kingston, whose last of two European Tour victories came in the Mercedes Benz Championship in 2009.
"I felt like I played half decent throughout the whole season, but just never managed to put a score on the board. It does make it a little harder to accept. Getting an invite into this event, what a great feeling to be back here. I think I've made the most of it today."
Ilonen had earlier survived everything the British summer could throw at him, including a brief spell of hail, to card a 67 as he looked to build on a run of two second places in his last three events.
"It was pretty nippy when we started and stayed that way," said Ilonen, who finished second in the Hassan Trophy and Volvo China Open recently.
"All day I was thinking 'Can I get these waterproof trousers off?' and never managed it. We even had hail on the ninth tee. I said to a friend last night it was going to snow today and she laughed at me. It's British summer and we have proof of that."
Henry, who only found out he was in the tournament as he boarded a flight from Madeira on Monday morning, completed a 68 which started with a bogey but also contained four birdies and an eagle.
"It was nice to see my name on the leaderboard on the back nine, it was a bit surreal," said the 26-year-old, who graduated from the Challenge Tour last season thanks to winning the Kazakhstan Open in a play-off.
"I was pretty nervous this morning, it's a big tournament and the first time I have been here. It's a great test of golf and for the first time this year I could put everything together."
All but one of last year's victorious Ryder Cup team are in the 150-man field, but several of them fell victim to the closing stretch at Wentworth - scene of the most controversial parts of Ernie Els' redesign in 2010.
England's Justin Rose - runner-up last year and beaten in a play-off in 2007 - finished bogey, double-bogey to drop from three under to level, while world number two Rory McIlroy had also been three under after 12 holes but bogeyed five of the last six to be home in 41 for a two-over 74.
Even reverting to a Scotty Cameron putter rather than use the Nike club he is contracted to following his multi-million pound deal in January did not help the world number two.
"It was one of those rounds that I let slip through my fingers," McIlroy said. "My hands were cold, I was wearing mittens all the way round trying to keep them warm, but I'm pretty unfamiliar with these conditions after playing in warmer climates."
McIlroy's playing partner Graeme McDowell - the pair are back on good terms after a minor disagreement over McIlroy's imminent change of management groups - also ran up a double-bogey seven on the 18th in matching McIlroy's 74.
Ian Poulter finished bogey-bogey in a 76, but Sergio Garcia at least enjoyed a moment of pleasure in a week so far dominated by a racism row involving Tiger Woods, the Spaniard holing from 20 feet for eagle on the last in a round of 72.