The miracle run of Argentina's Juan Martin del Potro continued Saturday in Rio de Janeiro, as he defeated Spain's Rafael Nadal 5-7, 6-4, 7-6 (5) in an instant classic to earn an opportunity to play for the gold medal in men's singles at the 2016 Summer Olympics.

Del Potro, who's battled consistent injury problems in recent years, became an afterthought after drawing Novak Djokovic in the first round. He started picking up steam after upsetting the top seed, however, and now he'll face Great Britain's Andy Murray, the reigning champion, for the coveted title.

Meanwhile, Nadal will play Japan's Kei Nishikori for the bronze medal as his marathon week of tennis continues for one more day.

The fact Nadal even reached the semifinals is a testament to his amazing internal competitiveness. He didn't advance beyond the third round of either of the season's first two majors and then missed Wimbledon as part of an absence that lasted more than two months leading up to the Games.

Christopher Clarey of the New York Times passed along comments from the 30-year-old Spaniard about the high level of success Friday night after he claimed men's doubles gold with Marc Lopez.

"Of course I did not want to miss the chance a second time to carry the flag," Nadal said. "But I didn't want to come and carry the flag and not compete. I wanted to come and take part if only in doubles, and then I decided to play singles, too, at the last minute. And things have gone really, really well."

The 14-time major champion dropped his first service game in lackluster fashion, and the immediate thought was that the heavy schedule might finally be getting to him. But, in typical fashion, he fought his way back into the opening set.

Nadal broke back in the sixth game, and just as the set looked destined for a tiebreak, he came through with a couple of clutch points to break Del Potro again in the final game to grab control of the match.

Jon Wertheim of Sports Illustrated joked about the amount of time the Spanish fan favorite has spent on the court this week:

Del Potro once again secured an early break in the second. This time around, he did a much better job of holding on to that advantage. He prevented Nadal, who started to show some signs of frustration, from even getting a look at a break point.

The biggest key in the set was the Argentine's success on his second serve. He only got 50 percent of his first-serve attempts in, but he won all 12 points on his second serve, which allowed him to stay out of trouble and get back level in the match.

David Law of BT Sport used a wrestling reference to describe the fight from Delpo:

The level of play and intensity in the third set was nothing short of extraordinary.

Every time it seemed like one player was starting to take charge of the points, the other one would fight back. There was no better example than when Del Potro broke late in the set to give himself a chance to serve for the match, only for Nadal to break right back.

There was one final look at a break for the Argentine as he raced to a 0-40 lead in Nadal's final service game, but he couldn't come up with the shot he needed to finish off the game. The Spaniard surged back to save his serve, and after a routine Del Potro hold, the match went to a deciding tiebreak.

In the end, Del Potro came up in the clutch with a couple of vintage laser forehands and rocket serves to win the breaker 7-5 and punch his ticket to play for the gold medal.

Ed McGrogan of Tennis Magazine commented on the match between two players who have been held back by the injury bug at a time when they could have made a strong era of tennis even better:

Looking ahead, Del Potro faces an uphill battle in the championship match against Murray. Not only does the Scot hold a 5-2 edge in their previous meetings, but he should also be the fresher player after a quick semifinal win.

As Howard Bryant of ESPN The Magazine tweeted, Del Potro isn't sure if he'll be ready for the matchup:

Even so, it's impossible to count out the Argentine after the week he's enjoyed.

Nadal holds a commanding 9-1 advantage over Nishikori, including a pair of straight-set victories in their two meetings in 2016. That said, the third-place matches are often more about which player is better able to recover mentally from the semifinal disappointment.

Post-Match Reaction

Afterward, BBC Sport passed along comments from Del Potro, who admitted even he didn't believe this type of run was possible.

"It means a lot to me. It's very big, maybe even more special than when I won the U.S. Open," the Argentine said. "I didn't expect to get to the final; I didn't expect to beat Djokovic. It's just amazing for me."

He added: "I am living a dream, and the crowd make me cry after every match."

All match statistics courtesy of the Olympics' official site.