Britain's Jonny Brownlee emulated brother Alistair by capturing the world triathlon title in Auckland.
The 22-year-old Olympic bronze medallist needed a top-three finish to win the title after taking a 180-point lead into the last of the eight races.
He came within two seconds of winning the grand final, beaten into second by Javier Gomez, but his overall score of 4,935 was 90 ahead of the Spaniard.
Alistair Brownlee did not compete after having his appendix removed last month.
Brownlee, two years younger than Olympic champion Alistair, was at the head of the field when the first competitors emerged from the cold waters of Auckland's Waitemata Harbour after the 1.5km swim.
Kris Gemmell of New Zealand, in his last world series event before retirement, attempted to break clear in the 40km cycle. He built a lead of more than a minute in blustery and wet conditions which left many areas waterlogged.
Russia's Alexander Bryukhankov, who entered the race placed third in the overall series standings, was forced to withdraw during the cycle leg.
Gemmell was quickly overhauled by Brownlee and Gomez, who ran most of the concluding 10km run shoulder to shoulder.
Gomez just managed to outsprint Brownlee at the end for a winning time of two hours and 29 seconds.
"It was a tough day today," said Brownlee, who won races in San Diego, Madrid and Stockholm this season.
"The bike was really, really hard and [in] the first bit of the run everyone was tired.
"The first two laps were nice and easy and then Javier attacked and it came to a sprint at the end and my tactics were shocking; I led him out into the wind and he just came past me.
"I am pleased the season's over; it's been a long year and I'm tired now."
Gomez said: "I knew it was almost impossible to be world champion here; Jonathan is a well-deserved champion. He had a really good season, pretty consistent and I did my job today.
"It's a good way to finish the season so I'm quite happy."
There was further British success as 23-year-old Non Stanford of Wales won the women's under-23 title on Saturday, finishing nine seconds clear of Sarissa De Vries from the Netherlands.
In the men's under-23 race, Britain's Tom Bishop claimed his second consecutive bronze medal, but last year's champion Matt Sharp missed out on the lead group on the bike leg and had to settle for sixth.
There will be highlights of the event on Sunday from 14:05-16:30 BST on BBC Two.
Men's Grand Final result:
1 J Gomez, Spain, 2 hours 00 minutes 29 seconds
2 J Brownlee, Britain, 2:00.31
3 S Riederer, Switzerland, 2:01.18
4 S Justus, Germany, 2:01.40
5 G Buchholz, Germany, 2:01.46
1 J Brownlee, Britain, 4,935 points
2 J Gomez, Spain, 4,845
3 D Polyanskiy, Russia, 3,822
4 S Riederer, Switzerland, 3,773
5 R Murray, South Africa, 3,575