Andy Murray wins historic second gold in epic final

The Briton added the Rio title to his 2012 triumph and to his grand slam collection of the 2012 US Open and 2013 and 2016 Wimbledon crowns.

It also stretched the 29-year-old's current winning streak to 18.

The final will go down as one of the best in the Olympics, lasting over four hours and ending with both men embracing at the net.

"Today was a very up and down match, very stressful. Both of us had a lot of chances and, it was a long and tiring match. I'm just glad I managed to get through it," Murray said.

He ended with 10 aces and 46 crunching winners while del Potro smashed 39 winners but was undone by 57 unforced errors.

Del Potro, a bronze medallist in London four years ago, was inconsolable at the end, weeping as he sat courtside.