Nikola Jokic felt he had proven his critics wrong after playing an astonishing 65 minutes in the Denver Nuggets' incredible quadruple-overtime defeat to the Portland Trail Blazers.

In only the second NBA playoff game in history to reach a fourth additional period, the Trail Blazers prevailed 140-137 to take a 2-1 lead in the Western Conference Semifinals series.

The only other postseason game to go that distance was when the Boston Celtics and Syracuse Nationals met in March 1953.

Jokic's marathon effort in a losing cause saw him play 64 minutes and 58 seconds, the most in a playoff game since that classic 66 years ago.

Incredibly, the seven-foot All-Star played 43 minutes and 58 seconds consecutively from halftime until the final seconds of fourth OT - finishing with 33 points, 18 rebounds and 14 assists – and had a message for critics who had previously questioned his fitness levels.

"They were talking about I'm not in shape!" Jokic told reporters, per ESPN. "I'm in really good shape. I don't know what they're talking about.

"Even when I came here [from Serbia] I was a little bit chubby. There's no difference even now. It's a basketball game. I'm feeling good."

Nuggets coach Michael Malone acknowledged he had asked for a lot from the 24-year-old.

"I mean, Nikola Jokic played 65 minutes," said Malone. "That's unheard of. That's ridiculous. I can't do that to him, that's too many minutes.

"[It was] an instant classic. It was almost like, when is this game going to end? It just kept on going and going and going."

Malone, who later added he had apologised to Jokic, continued: "If I was at home watching this game, I would've been glued to my TV. This was a great basketball game. [It] wasn't pretty at all times, but the effort, the competitive spirit from both groups was outstanding.

"We fought, we fought, we fought. That's all you can ask for. [We gave up] too many second-chance points, too many turnovers, that was the difference in the game. But that was a hell of a basketball game by two very good basketball teams."

After his side emerged victorious, the Trail Blazers' Maurice Harkless could not believe what he was reading on the stat sheet.

"Sixty-five minutes, that's crazy," he said of Jokic. "There is a lot to process, honestly."