After just over three hours on court a weary Kuznetsova tugged the ball wide to hand Konta a thrilling 3-6, 7-5, 7-5 victory.
"That's the longest match I've had for ages! I've been very fortunate to be part of some spectacular matches in my career and that definitely ranks up there because it's my first Olympics," Konta said.
Konta has been playing the tennis of her life this summer, but for the first hour against Kuznetsova it looked like this hectic schedule was finally catching up with her.
Trailing 2-0 in the second set, Konta's punchy groundstrokes finally began to penetrate her opponent's defenses, a run of four straight games hauling her back into the contest. Despite surrendering this advantage, the Briton hit back to level the match and then forge ahead in the decider.
Kuznetsova has enjoyed an enviable career, yet has failed to end either of her previous Olympic campaigns on the podium. And even when the cause appeared lost, her desire for this missing medal ensured a tense finale.
Serving for the match at 5-3, Konta came within two points of victory only to falter. This saw the momentum swing back towards the Russian and in Konta's next service game she carved out three more break points.
Back came the World No.13, a sequence of fearless ball striking enabling her to edge ahead once more. With the finishing line within reach once more, Konta's nerves reappeared, squandering three match points closing out a famous victory at the fourth time of asking.
Konta, who was ranked outside the Top 200 four years ago, is making her Olympic debut and has found it hard not to become swept up in the spirit of the Games: "Well once you get on court it's about the opponent, it's about yourself, it's about competing. But I do think there are slight differences especially this year there are no ranking points. A lot of players play inspired when it comes to their country and that's how it should be."
? BBC Sport (@BBCSport) 9 August 2016