The Serbian triumphed 7-5, 4-6, 7-6, 6-7, 6-3 after 4 hours and 43 minutes – the longest Wimbledon semi-final ever – and will go for a second title at the All England Club tomorrow.
But the scoreline barely hints at the astonishing drama that unfolded during a pulsating encounter on Centre Court between two players at the height of their talents.
Del Potro produced some of his finest tennis since lifting the 2009 US Open, hitting forehand winners that consistently topped 100mph, while Djokovic’s beguiling determination to return every shot boggled even the minds of those used to witnessing his amazing feats of stretching.
The Argentine saved two match points during the fourth set tiebreak which was a mini-drama worthy of the admission fee all by itself.
It was comedy at the most tense of moments as match point was saved. Del Potro rescued another on his own serve, then won the next two to take the set.
The decider saw no let up in the quality and reached 4-3 to Djokovic, who then summoned the strength to break Del Potro with remarkable defence that left the 24-year-old looking crestfallen.
Djokovic had to save a break point as he served for the match before finishing off the match in fitting fashion, with a backhand winner down the line. A standing ovation in tribute to both was the only possible response.
Djokovic is no stranger to five-set thrillers but he said:
‘This is definitely one of the best, no question about it. Exciting here at Wimbledon. I’m privileged to play this match.’
The previous longest last-four encounter was the 1989 match between Boris Becker and Ivan Lendl, which Becker eventually won.
“It was one of the best matches I’ve been a part of,” said Djokovic, winner of the men’s singles at Wimbledon in 2011.
“I could not separate us, apart from when I was 2-1 and a break up – and I dropped serve.
“That’s why he’s a Grand Slam champion. He came up with some top shots, credit to him.”
Serbia’s Djokovic, who was playing in his 13th consecutive Grand Slam semi-final, is bidding for his seventh major title.
Before Friday’s match on Centre Court he led Del Potro 8-3 in head-to-head encounters but was beaten by the Argentine in last year’s Olympic bronze-medal match, held at Wimbledon.
Del Potro was not even sure if he would be able to play after aggravating a knee injury in his quarter-final but he held his own for much of the first set.
However, with the score at 6-5 Djokovic, 26, found another gear, managing to break the Argentine for the first time in the tournament.
But Del Potro, the 2009 US Open champion, refused to wilt, breaking his rival to love to lead 4-3 in the second set.
Del Potro, 24, staved off a break point in his next service game and went on to level, to the approval of the Centre Court crowd.
With the score at 3-3 in the third set Del Potro had two break points but netted with a volley on the first and narrowly missed with an attempted backhand pass on the second.
As the match wore on the baseline exchanges became ever more punishing and one scrambled forehand by Del Potro had Djokovic smiling wryly in disbelief.
The Serb was smiling again when Del Potro saved the third of three set points with a heaved forehand that skimmed the baseline.
But it was Del Potro who buckled in the third-set tie-break, which Djokovic secured courtesy of a flicked backhand winner from behind the baseline. — BBC Sport/Mailonline.



