Juggling stifling humidity with adjusting to new equipment, weather disruptions and fatigue, reigning Masters champion Sergio Garcia somehow put everything together for a runaway five-stroke victory at the SMBC Singapore Open yesterday.

As his rivals wilted in the 32 deg C heat at Sentosa Golf Club's Serapong course, the Spaniard remarkably played 27 holes over two rounds without dropping a shot, netting seven birdies in the process for a four-day total of 14-under 270.

His final-round three-under 68 was tied for the second lowest of the day, with only one quarter of the 68-strong field going under par in tough scoring conditions.

"What a day. I'm going to sleep well tonight. It was not easy playing 27 holes in this heat. It might have looked easy, but I still had to hit a lot of good shots," said Garcia, who returned to Serapong just after dawn to complete the last nine holes of his weather-delayed third round, going four under in that stretch.

"It was a tough week too with all the stopping and going on (from the lightning disruptions in the first three days) but obviously extremely happy with how it went."

The 38-year-old had only three bogeys in 72 holes and hit 65 of 72 greens in regulation for the tournament, as he made a seamless transition to his new Callaway equipment.

Even his management of the scorching conditions was exemplary, as Garcia ducked under an umbrella handed to him by his caddie whenever not hitting a shot.

"You always have to be careful with things like heatstroke, so that's why I had my umbrella out a little bit," said Garcia, who finished 11th last year in his Singapore Open debut. "I had (a brush with) heatstroke in Australia at the end of last year (at the Australian PGA Championship) and I was like a zombie moving around."

Satoshi Kodaira (71) and Shaun Norris (70) were distant runners-up to Garcia at the US$1 million (S$1.32 million) event with 275s.

Neither managed to mount a realistic challenge for the lead, with Kodaira mixing five birdies with five bogeys and Norris moving up the leaderboard only in the last six holes, when he had three birdies.

Kodaira should have perhaps deployed his umbrella more often.

Said the six-time winner on the Japan Golf Tour, who was briefly on 10 under at the fourth hole: "I played well on the front nine, but then had some bad misses on the back nine (three-putting for bogey on the 13th). Maybe because it was just too hot.

"I couldn't reach Sergio in the end. I was thinking 12 or 13 under for the win, but he went under that."

Thais Jazz Janewattananond (71) and Danthai Boonma (73) also struggled to keep their scores down, but did enough to tie for fourth on 276.

With the Singapore Open part of the 147th British Open Qualifying Series, Jazz and Danthai secured themselves a spot at Carnoustie in July, alongside American Sean Crocker (277) and Australian Lucas Herbert (278). The four were the best finishers in the field who had not already qualified.

Herbert got the last slot by virtue of his higher world ranking than Filipino Miguel Tabuena and American Berry Henson, who also finished on six under.

A total of 30,000 fans turned up this year, up from 25,000 last year.