Andy Murray beats Juan Martín del Potro to win second Olympic gold

• Team GB flag-bearer defeats resurgent Argentinian 7-5, 4-6, 6-2, 7-5
• World No2 retains Olympic singles title he won at London 2012

Britain’s Andy Murray celebrates after retaining his Olympic singles title, beating Argentina’s Juan Martin Del Potro in the Rio final. Photograph: Luis Acosta/AFP/Getty Images

Europeans have often come to grief looking for gold in South America but, although Andy Murray flirted too often with disaster, he conquered his nerves and, after four sets of agonising fluctuations, Juan Martín del Potro to strike the mother lode again in Rio on Sunday night.

He remains the Olympic men’s singles champion, the first in the history of the sport to win the prize back to back. “I did it for my country,” he said in London four years ago. The conviction and commitment has only strengthened since. In a match that lasted 4hr 2min, he won 7-5, 4-6, 6-2, 7-5. But the score could have been anything, so wild a night was it.

Murray sat on his bench and sobbed into his Olympic towel. So did the loser. So did a few others, more than likely.

It was a final riddled with enough drama to compensate for the serial imperfections of both players. There were 15 breaks of service, many of them consecutive, eked from an astonishing 35 opportunities, as well as 102 unforced errors, shared roughly equally. Game points came and went, squandered mostly, rather than stolen. This was a fight that either of them could have won or lost several times over.

Del Potro – who had seen off Novak Djokovic in straight sets in the first match of the tournament and Rafael Nadal in three hours and eight minutes of hell in the second semi-final – was never going to be intimidated, even though many expected him to fold.

Some very good players chose not to come, for a variety of reasons. These two players had no doubt that they care about being here. Murray tried everything to break the big man down: he chipped, lobbed, played soft-ball and hard-ball, wide and deep. He served with flat power and subtle spin, although his 51% return was poor. Perhaps there was too much variety. Maybe he should have just kept it tight. Certainly, it was entertaining and unpredictable.

From the start, Murray gave Del Potro’s new backhand slice a proper working over and the Argentinian, corralled in the ad corner for nearly quarter of an hour, cracked after saving three break points but not a fourth.

The crowd dynamic was fascinating. Those Brazilians present among the 10,000 spared no affection for their southern neighbour, so Murray had a discernible edge in support, which was fevered throughout. Del Potro still had plenty of friends – the light blue and white flags outnumbering the Saltire and Union Jacks by about 20-5 – and they were roused when he broke back, shattered when he hit long to give up his serve a second time, then back on song when a Murray double fault and a botched backhand in the seventh game gave their man encouragement.

Often it seems Murray saves his bursts of genius for a crisis, minor or major, and just past the hour he found enough to haul himself out of the doldrums, holding through deuce then breaking Del Potro for a third time, with a sublime backhand down the line, to take the set. He had made hard work of it, though.

What he needed now was not emergency fixes but the sort of steady, leg-sapping tennis that dragged him back from the precipice against Fabio Fognini and Steve Johnson earlier in the week. However, he struggled still for rhythm. When Del Potro scampered from deep but failed to hunt down a drop shot in the first game of the second set, he dropped his head and arms on the net, grimaced and sucked at the air for fully 30 seconds. Yet, two points later, he passed Murray at the net to break.

Was this the start of a glorious fightback, such as he produced against Nadal over three hours and eight minutes the evening before, or a flickering of the flame? He held under the most intense pressure, seeming out on his feet yet refusing to surrender.

This was an odd passage of play for Murray. He could see his opponent was suffering, although still firing back intermittently and with some venom, while his own game, particularly his serve, was not functioning at the very time he could have taken the play away from Del Potro with ease.

On appearances alone, the prospect of Del Potro remaining competitive beyond three sets seemed negligible, yet he was still dangerous, still punching, still willing. When he held for 4-2, he fist-pumped determinedly, knowing the long haul would bring pain but perhaps glory. Both were now suffering, but in different ways.

Del Potro’s legs might have been screaming at him, but his strong right arm – the one whose wrist had collapsed and forced him into a long, dark struggle to get back to his best – was buzzing. And what heart he showed to wear down Murray with power and persistence in a long 10th game to take the set with a killer forehand into the deuce corner.

Now, after two-and-a-quarter hours, they could start again on level terms: best of three – like the disparate battles they had endured to get here. There was no obvious favourite; Del Potro’s demeanour had lifted noticeably, but Murray had that mean look about him when cornered. He charged Del Potro’s second serve at the end of the sixth game, forcing an error and break point, then yelled in delight when the Argentinian hit long.

Emboldened – or maybe fired by a mixture of anxiety and frustration – Murray began to press hard at the net, and was alive to every possibility for a quick kill. Gradually the careless shots lessened. The focus gradually returned, and he began to look way more comfortable than he had for at least an hour. Del Potro, simultaneously, started to fade – this time more dramatically than before, and Murray pounced. He rifled an unreachable forehand return off a tired second serve and the set was his.

The first set had lasted an hour-and-a-quarter, the second an hour and this one 36 minutes. The job was not getting that much easier, just a little more straightforward. If Murray could keep his foot on Del Potro’s throat for another half or so, the medal was his.

Small groups of Argentinian supporters began to slip away, in the manner of football fans resigned to their fate and keen to beat the traffic. One Argentinian was going nowhere, though. In a bizarre stretch of four consecutive service breaks, he went with Murray mistake for mistake, winner for winner. This was not a match to walk away from.

Murray was the first to hold serve in this weird fourth set, but gambled needlessly at the net to hand Del Potro parity in the sixth game. Suddenly there was a spring in the big man’s step. He lured Murray into an injudicious lob, smashed it as if cracking a walnut to break again, and cries of “Argentina! Argentina!” whistled around the arena.

Serving to stay in the match in a long and tortuous 10th game, Del Potro looked utterly spent as he plugged the net with a closing backhand to hand Murray yet another reprieve.

At 30-30 in the 12th game, two points short of the medal, Murray faltered in the shot when someone shouted from the crowd. Soldiers led the miscreant from the fray at deuce. He was wearing a jester’s hat, and grinning like an idiot.

Murray got match point – and netted. Del Potro did likewise. Of course he did. They had been doing this all night. And then the show was closed. Del Potro found the net one time to many. The clown had gone. The players took their bows and embraced. Del Potro looked as if he might fall over if he let Murray go. They smiled the smile of champions who had given it all.