As a storm brewed overhead, Ernie Els completed another electric display at the Johnnie Walker Classic to land his fourth title in five incredible weeks.

The thunder and lightning over Perth held off long enough for Els to shoot a final round of 66 to win by an emphatic 10 shots with a record-breaking 29-under-par.

In 13 years as a professional Els has never played better than he has this year and the records are beginning to tumble.

His 2003 season began with victory at the Mercedes Championship in Hawaii, which he clinched with a USPGA Tour record score of 31-under-par.

And on Sunday he set a new mark for the European and Asian tours, beating the respective records of 27-under-par with another wire-to-wire victory.

"It has been an unbelievable week. We came in after a nice week's holiday and I felt like playing, but I never thought I would be shooting that kind of score," he said as the thunder rumbled and heavens opened.

"I am really delighted by the way it all worked out. This week everything went right.

"I had a great time. The greens are soft, the wind stayed away all week and I could just go out there and attack the golf course.

"The way I am playing now is some of the best golf I have ever played. The whole package is pretty good at the moment."

Els' nearest rivals were Australians Stephen Leaney and Andre Stolz, who finished tied for second on 19-under for the tournament.

But from the first morning, when Els scorched the back nine in just 29 strokes, he was unstoppable.

He dealt successfully with the pressures of leading for the entire tournament, extending his cushion at the top of the board with each passing round.

Last year, when the course was distinctly more testing, Retief Goosen led by 13 shots into the final day. Els' cushion on Sunday was nine.

"You've got all that tension every day, most of the pressure every day," he said.

"Everybody is waiting for your mistakes and hoping for mistakes. So yes, it is difficult playing with the lead from day one but it is something that I would like to get used to."

The battle for second place was fierce but though Els wavered a little early on, the gap remained healthy.

He saved par with a brilliant recovery from the banks of the lake on the third hole and had picked up one shot by the time he entered the back nine.

His success on the homeward stretch was the foundation of his victory and he picked up another five shots to finish an incredible 22-under-par for the 36 holes played.

"I hit a couple of iffy shots at the start of my round but I got away with a couple of pars on two and three," he said.

"Today I felt very comfortable. The start was so-so, but I think from four in I hit the ball as good as I've hit it all week.

"It was an excellent day, an excellent week. It is nice to finish the tournament off in a good way."

The jostling for position behind Els was intense but in the final shake-up it was Leaney and Stolz who shared second place after both carded 66s.

"I am very pleased," said Leaney, the German Masters champion.

"If somebody had said at the start of the week I would have shot 19-under-par and lost by 10 I would have been pretty upset, but what can you do? I can't play any better than that."

Two shots back, five players tied for fourth on 17-under-par.

Goosen was disappointed to relinquish his title with an "inconsistent" performance but Justin Rose, who made a late dash up the leaderboard, was delighted with his third consecutive top 10 finish.

The 22-year-old had been named as the Johnnie Walker Young Player of the Year the previous night and proved the panel made the right decision with a 65.

Also on minus 17 was Australia's Robert Allenby, New Zealander David Smail and Jean-Francois Remesy, who dropped two shots on the last three holes.

Remesy had been tied for second after 54 holes, but had already conceded Els was well out of sight.

Els' recent form reads five victories and a second place in his last six tournaments, stretching back to the Nedbank Challenge in South Africa before Christmas.

His season began with that victory at the Mercedes Championship followed by another at the Sony Open.

The only time he has been beaten in 2003, Els led up the final fairway of the Singapore Masters but was trumped by China's Zhang Lian-Wei, who birdied as he bogeyed.

Els then flew into Melbourne and retained his title at the Heineken Classic before making it four from five in 2003 at Lake Karrinyup.

His four titles in five weeks have earned Els a cool £1.43million and one Tiger Woods, making his season debut at the Buick International, will be looking anxiously over his shoulder.

Collated final-round scores (Par 72, Gbr and Irl unless stated):

259 Ernie Els (Rsa) 64 65 64 66

269 Stephen Leaney (Aus) 68 67 68 66, Andre Stolz (Aus) 68 68 67 66

271 Justin Rose 68 69 69 65, Robert Allenby (Aus) 69 64 72 66, Retief Goosen (Rsa) 72 65 66 68, David Smail (Nzl) 68 71 64 68, Jean-Francois Remesy (Fra) 68 67 67 69

272 Niclas Fasth (Swe) 74 65 66 67, Craig Kamps (Rsa) 71 67 64 70

274 Ignacio Garrido (Spa) 69 69 68 68, Michael Long (Nzl) 71 66 68 69, Nathan Green (Aus) 73 68 64 69, Craig Spence (Aus) 73 68 63 70

275 Craig Parry (Aus) 68 69 72 66, Chris Downes (Aus) 67 73 68 67, Robert Karlsson (Swe) 69 71 66 69

276 Paul Casey 71 70 67 68, David Howell 71 69 67 69, Paul Mcginley 67 71 68 70, Simon Yates 72 68 65 71

277 Brett Rumford (Aus) 67 73 67 70, Trevor Immelman (Rsa) 73 68 66 70, Terry Price (Aus) 66 71 69 71

278 Peter O'malley (Aus) 67 75 68 68, Charlie Wi (Kor) 72 71 66 69, Scott Gardiner (Aus) 74 69 65 70, Jamie Donaldson 68 71 69 70, Greg Owen 69 64 74 71, Bradley Hughes (Aus) 75 67 65 71, David Lynn 65 72 68 73

279 Tony Carolan (Aus) 72 70 68 69, Jarrod Moseley (Aus) 70 71 68 70, Paul Sheehan (Aus) 68 71 69 71

280 Steen Tinning (Den) 72 70 69 69, Clay Devers (USA) 70 72 66 72, Henrik Bjornstad (Nor) 69 71 66 74

281 Arjun Singh (Ind) 68 71 71 71, Arjun Atwal (Ind) 73 69 68 71, Marcus Norgren (Swe) 70 71 70 70, Alastair Forsyth 73 69 70 69, Ian Woosnam 67 71 75 68, Nick Dougherty 73 66 74 68, David Gilford 71 72 71 67, Nick O'hern (Aus) 74 68 72 67

282 Soren Kjeldsen (Den) 73 67 71 71, Raymond Russell 70 70 71 71, Kevin Na (Kor) 71 72 69 70, Gary Evans 70 71 71 70, Jonathan Lomas 73 70 70 69, Adam Crawford (Aus) 71 72 70 69, Nick Faldo 68 74 71 69, Jyoti Randhawa (Ind) 72 69 73 68, Andrew Bonhomme (Aus) 71 70 69 72, Raphaël Jacquelin (Fra) 68 74 67 73, Marcus Cain (Aus) 69 72 67 74

283 Peter Fowler (Aus) 70 73 68 72, Santiago Luna (Spa) 70 69 72 72, Brian Davis 71 70 70 72, Warren Bennett 71 68 73 71, Stephen Scahill (Nzl) 70 73 71 69, James Kingston (Rsa) 72 69 69 73, Thomas Bjorn (Den) 68 74 67 74

284 Grant Dodd (Aus) 71 71 70 72, Richard Green (Aus) 71 69 72 72, Patrik Sjoland (Swe) 75 67 72 70

285 Andrew Pitts (USA) 74 69 70 72, Ian Poulter 74 69 70 72, John Bickerton 70 68 75 72, Darren Fichardt (Rsa) 70 72 68 75

286 Andrew Tschudin (Aus) 70 72 70 74, Barry Lane 74 68 72 72, Eddie Lee (Nzl) 73 70 73 70

287 Matthew Ecob (Aus) 72 71 71 73, Edward Loar (USA) 72 68 76 71

288 Mardan Mamat (Sin) 69 72 73 74

289 Ted Oh (Kor) 71 72 74 72

290 Michael Sim (am, Aus) 72 71 71 76, Mark Allen (Aus) 73 69 72 76, David Gleeson (Aus) 71 72 72 75

291 Anthony Wall 72 71 71 77, Gary Simpson (Aus) 72 70 76 73