LONDON — Novak Djokovic might win Wimbledon this year. Juan Martin del Potro will not.
No matter how it ends, both men will always have their spot in one of the most memorable matches in the storied history of the All England Club.
Slugging back and forth over 4 hours, 43 minutes of withering, backbreaking tennis Friday, top-seeded Djokovic emerged with a 7-5, 4-6, 7-6 (7-2), 6-7 (6-8), 6-3 victory over del Potro to move one victory away from his seventh major title.
‘‘One of the best matches I’ve been a part of,’’ Djokovic said. ‘‘One of the most exciting definitely. It was so close. You couldn’t separate us. Exciting.’’
It was the longest semifinal in Wimbledon history and was only five minutes short of the 2008 five-set final between Roger Federer and Rafael Nadal that’s also considered one of the greatest matches played on Centre Court.
On Sunday, Djokovic will play second-seeded Andy Murray, who defeated No. 24 Jerzy Janowicz, 6-7 (2-7), 6-4, 6-4, 6-3, to make his second straight Wimbledon final and move one win away from becoming the first British man in 77 years to capture his country’s home tournament.
This will be their third meeting in the last four Grand Slam finals. Murray won at the US Open last year and Djokovic won in Australia this year. On Murray’s mind every bit as much, however, will be his 7-5, 7-5 win on Centre Court last year in the Olympic semifinals.
‘‘I'll take that thought to my head when we play on Sunday,’’ Murray said.
With skies starting to darken, the Murray match was interrupted for a half-hour while the roof was closed over Centre Court. Murray protested the delay, saying there was still sunlight left. He had other reasons, too. He had just rolled off five straight games to close out the third set after falling behind 4-1.
‘‘It’s a tough situation,’’ Murray said. ‘‘There were probably 45 minutes of light left. I'd like to think this is an outdoor event and you try to play as much as you can outdoors. But I managed to regain focus. I took a shower, talked to the guys a little bit and got back to it.’’
Now Murray has time to think about facing Djokovic and the possibility of a Wimbledon championship.
‘‘I might wake up on Sunday and be unbelievably nervous, more nervous than I ever have been before,’’ Murray said. ‘‘But I wouldn’t expect to be.’’
The late finish came courtesy of what had been billed as the undercard, but turned into something much better.
Djokovic and del Potro spent the entire, sundrenched afternoon exchanging huge groundstrokes, long rallies and even a few laughs during their marathon, which covered five sets, 55 games, two tiebreakers and 368 points.
Eighth-seeded Del Potro, back in a Grand Slam semifinal for the first time since winning the 2009 US Open, saved 2 match points in the fourth-set tiebreaker, then won the final 4 points to take it 8-6.
Shortly after, the match hit the 4-hour mark, guaranteeing it would surpass the 1989 match between Boris Becker and Ivan Lendl (4 hours 1 minute) as the longest semifinal in Wimbledon’s long history.
‘‘It was a very high level of tennis today, I expected it,’’ said Djokovic, whose 80 winners included 22 aces. ‘‘I was ready to play five sets and I stayed tough until the end.’’
Del Potro came into the match with his left knee heavily taped, a victim of two nasty slips that sent him tumbling earlier in the tournament. The second fall came two days earlier, on the fifth point in the quarterfinal against David Ferrer. Del Potro said his trainer gave him a couple of ‘‘magic pills’’ — anti-inflammatories — and that kept him going in his straight-sets win over the No. 4 seed.
On Friday against Djokovic, del Potro showed few signs of an aftereffect.
Tested throughout by a variety of Djokovic drop shots, del Potro got to most. More than once, the Argentine did his impression of a lanky golden retriever — chasing the tennis ball from wide of the court on the forehand side to wide of the court on the backhand side. After going wide in the third set to hit one of his 48 winners, del Potro stood on the ledge separating the court from the stands, waiting for a high-five from one of the fans at courtside.
‘‘In tough situations, he came with some unbelievable shots,’’ Djokovic said.
There were a few he’d love to have back. Trailing, 3-2, in the third-set tiebreaker, del Potro failed to put an overhead away and Djokovic slipped and fell on the dirt behind the baseline while throwing up a weak lob. Backpedaling, del Potro couldn’t handle the overhead and dropped it in the net. He lost the rest of the points to fall behind by a set.
A bit later, Del Potro lost his serve to fall behind 4-3 in the fourth set, but broke right back, finishing the game with a big backhand winner, a guttural grunt and a fist pump.
They held serve until the tiebreaker, and when del Potro won that one, he looked like the del Potro of 2009, the man who broke the Federer-Nadal-Djokovic stranglehold on the majors by overcoming a 2-1 deficit against Federer in the final at Flushing Meadows to win the title.