The 35-year-old, who also won silver in 1996, has now overtaken Dane Paul Elvstrom, who won four golds up to 1960.

Ainslie's teammates Iain Percy and Andrew Simpson were denied a successive Olympic gold in the Star class as Sweden won the final medal race.

The British pair had led going into the final but an eighth-placed finish meant silver for them as Sweden's Fredrik Loof and Max Salminen came through to win the race and title.

Ainslie had given himself a massive task earlier in the week as he failed to win any of the first six races in the Finn class, but he dug in characteristic fashion to recover his fortunes, and was able to secure the gold by finishing ninth in the tense, concluding medal race – which scores double points - pushing the man who had led the regatta for most of the week, Jonas Hogh-Christensen of Denmark, into the silver medal position.

France's Jonathan Lobert knocked Dutchman Pieter-Jan Postma out of the bronze medal position on the final run to the finish.

Gold seemed uncertain for Ainslie as Jonas Hogh-Christensen led in the Finn class earlier this week

"It's times like this you are supposed to come out with something clever but I can't think of anything – I am speechless," said Ainslie.

"I am just so glad for everyone who has supported me over the last four years; it has been an amazing Olympics.

"After six races I was in a bit of trouble.

"Thankfully I turned things around and got it right when it counted.

"This was one of the hardest courses I have raced on and I don't want to do anything like that again.

"You can never say never, but I don't think I can sail one of these again, it's killing my body so I don't think you will see me in Rio [for the 2016 Olympics].

"But it's the best way to bow out at a home Olympics.

"I learned to sail for fun so it's been a long road but I have had a lot of support over the years and I am just so glad to have done it.

"It's been incredibly hard - there's a huge amount of pressure to perform at a home Games.

"It's been the hardest couple of weeks of my life but you just have to get on with the job."

Ben Ainslie celebrates winning his fourth gold in Weymouth

After failing to beat Hogh-Christensen in the first six races, Ainslie employed what might or might not have been a little mental pressure in telling the press that Christensen and Dutchman Pieter-Jan Postma had teamed up against him in race two, forcing him to do a penalty turn.

"They've made a big mistake," he said.

"They've made me angry and you don't want to make me angry."

The phrase echoed policeman John Book's warning in the film Witness to the jeering teenager who smeared ice cream on his face, thinking he would get no come-back as Book was wearing the garb of the peace-loving Amish people.

The teenager got a broken nose.

Ainslie earned his first victory of the series a day after watching Heather Stanning and Helen Glover win Britain's first gold of the Games at the rowing, with Bradley Wiggins adding a cycling time trial gold soon after.

"I thought to myself, if they can go out and do that, why can't I?" he said.

"You see British people performing really well at the highest level and it inspires you to do the same."

Percy, 36, who won his first Olympic gold in the Finn class at the 2000 Sydney Games, said: "It feels cruel sometimes.

"It was ridiculous conditions at the end.

"We feel a little robbed, but that is the way it goes.

"We're hurting so much inside but it makes it so much easier to know [the supporters] are so happy for us.

"The crowd for me today is going to be a highlight of my life and probably the only thing that puts a smile back on my face."

Britain's Simpson & Percy, sail past Switzerland's Enrico de Maria and Flavio Marazzi, in the Star sailing class

Simpson, 36, added: "You are never 100 per cent confident.

"We didn't get it right and can't blame anyone but ourselves.

"We had a great regatta overall, and we are really frustrated.

"We tried our hardest, but it wasn't to be."

Brazil's Robert Scheidt and Bruno Prada slipped from silver to bronze after coming seventh in the medal race.

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