Andy Murray admitted the whole Olympic experience had been amazing but draining following his four-set, gold medal-winning victory over Juan Martin Del Potro in the singles final on Rio’s Centre Court on Sunday night.

Murray broke down in tears after his victory, which took four hours, featured a glut of unforced errors, poor serving, brilliant, exhausting rallies and drama galore.

The final set featured seven breaks of serve out of 12 games before Murray broke for the decisive time to seal his second gold after his victory four years ago in London.

“I was very emotional at the end,” Murray said. “It has been a build-up of emotions. I was just happy to get over the line. I’m just so tired. Carrying the flag was amazing. I am honoured to have done that and I was emotional on the day and the day after. I had to sort of regroup and get my mind on the matches and to finish with a match like that was tough.

“I was tired. We played for four hours on a hard surface and it was humid. The slow court means you do a lot of running, too. I didn’t serve well which made the match tougher than it was already. But I managed to get through it. I pulled off some big holds when I was facing break points. Especially at 5-5 in fourth set.”

That was the key moment. Murray then broke Del Potro for the match in the next game when for all the world it had looked like going into a fifth.

Murray was not in a position to rank his second gold in terms of victories in his career but could say it meant a huge amount to him. “I’m really happy,” he said. “It’s not for me to say [where it ranks]. I can’t answer that. I can say it was one the hardest matches I’ve had for a big title. Against Novak Djokovic for my first Slam [at the US Open in 2012] was very hard.

“But tonight was difficult emotionally, it was physically hard. It was one of the toughest matches I’ve played to win a big event.”

The crowd in the 10,000-seater Centre Court was a split of pro-Del Potro Argentinians and anti-Del Potro (and therefore pro-Murray) Brazilians and it made for an amazing - and unique in tennis terms - atmosphere full of chanting and booing. Murray loved it.

“It was a great atmosphere,” he said. “There were not many problems. The crowd was split and we rarely have that. Normally at Slams the crowd come to watch great tennis are not on one side. We don’t hear songs and chanting and then booing when they are singing. The Davis Cup is a home tie so the majority are supporting the home team. It is rare to have a split and it makes for a great atmosphere.”

How did winning Rio 2016 compare to winning London 2012?

“Very different. [London] was the first time I’d won any major event,” he said. “It was a home Games and it was an amazing time for me, especially after losing the Wimbledon final just before. It was much harder here. The final in 2012 was much more straightforward [when he beat a tired Roger Federer who had a gruelling semi-final against Del Potro].

“Here anything could have happened. There were lots of breaks and ups and downs.”

Back-to-back Olympic titles have never been won before Murray achieved it here. Would he be around to go for gold again in 2020?

“Tokyo? Who knows?” he said. “I’ll be 33 and I don’t suppose I’ll be playing at the same level. The fact it has not been done before shows it is difficult. A lot can happen in four years. Since London I’ve had back surgery, my ranking dropped... I’m just happy that I’m still here now and competing for the biggest events.”

And now rather than revel in the glory of gold Murray is off. “Sadly I won’t get to enjoy it, I play again in 48 hours,” he said before flying on Sunday night to America to play in the Cincinnati Masters as he builds up to the next goal: the US Open. He has not lost in 18 matches and that consistency could lead to more Slam joy.

“The last few months, since Monte Carlo in April really, I’ve been there or thereabouts in the biggest events,” he said. “I’ve had good wins against top players. Novak over two years has shown amazing consistency. I’ve done it over four months - he does it over a whole year and that’s my aim.

“For now the US Open is the next big goal. I’ve been in the finals of all the Slams this year but was disappointing in last year’s US Open final. I’ll try to have a better one this time.”

Gold in his pocket, he is already looking ahead.