Neither Argentina nor Switzerland have won a medal so far at these Games and the pressure visibly told on both men but in the end, Federer’s serve and defense won out over del Potro’s firepower and heart. In windy conditions, del Potro — competing in his first Olympics on his least favorite surface, against a man who has beaten him 5 times this year alone — played a sublime first set, dictating from inside the baseline, reading Federer’s serve and finishing points off at the net, demonstrating how significantly he has quietly improved on the grass. He had chances to press that advantage in the second set, but Federer — down break points at 2-2 and 4-4 — produced aces and unplayable first serves in his signature style to keep himself in the match. As the quality of play dropped, the momentum shifted in Federer’s favor and he led the second set tie break from the start, taking it 7-5 with an ace after del Potro put a routine backhand long to give up the mini break.
A devastated del Potro cradled his towel-wrapped head in his hands on the changeover, but regrouped strongly and it was Federer who failed to press his advantage early in the third, having to save break points at 0-1. The combination led to the marathon third set which broke Olympic and Open-era records as neither man could break serve. Del Potro was in the more precarious position throughout as Federer continued to serve brilliantly; the Argentine had to save break points at 3-3, then 4-4, then 7-7, his struggles punctuated by love or routine holds from Federer. At 8-8, only a diving stab volley winner saved del Potro from being 0-40 down and at 9-9, he double-faulted twice before two backhand errors gave Federer the break.
Remarkably, however, del Potro regrouped for a clean, aggressive game and it was Federer’s turn to make two backhand errors to be broken back to love. Serving from behind, Federer continued to come up with impenetrable service holds and unplayable deliveries, successfully holding to stay in the match 12 times and looking increasingly the fresher player both physically and mentally. It was a remarkable display with his back against the wall and although del Potro came back from 0-40 to hold at 14-14, then 0-30 at 15-15, something had to give and it was clearly not going to be Federer’s serve. Breaking after a long backhand from del Potro, Federer served for the match for the second time an hour after his first opportunity and this time, despite a double fault and a flubbed volley on his first match point, he would not be denied.
Del Potro will have to somehow pick himself up, after yet another crushing defeat in which he gave his all and fell short, to play for a bronze medal. Federer meanwhile has a day to recover before the final against either Djokovic or Murray, both men he beat on Centre Court a few weeks ago. That gold medal must feel very close now.