Novak Djokovic came back from a set down and defeated his young rival Carlos Alcaraz 4-6 6-4 6-3 6-4 at 12:57 p.m. and qualified for the semi-finals of the Australian Open.
In the latest chapter of a generational rivalry played out on the biggest stages, including last year's gold medal match at the Paris Olympics, the 37-year-old Djokovic maintained his hard-court dominance over Alcaraz to reach a landmark 50th Grand Slam semi-final against Alexander Zvereza.
Coach Andy Murray, sitting in a courtside pot, also deserves credit as this was a tactical triumph as Djokovic blunted his opponent's firepower and spirit before the 21-year-old produced a spectacular breakaway.
The defeat was a blow for Alcaraz as the French Open and Wimbledon champion's bid to become the youngest man to complete a career Grand Slam was on fire and he was left to digest his third loss to Djokovic on the surface.
“First I want to express my utmost respect and admiration for Carlos and everything he stands for – and what he has achieved so far in his young career,” said Djokovic.
“What a great guy he is and an even better competitor… I just wish this match today was the final, honestly.
“This is one of the most epic matches I've played on this court – on any court, really.”
A potential concern for Djokovic is a left leg problem that required treatment during the first set, but he appeared to improve physically as the match progressed.
“Since I'm still in the tournament, I don't want to reveal too much,” he said. “The medicine started working and it helped without a doubt.
“If I had lost the second set, I don't know if I would have continued playing. But I felt better and better, and I played some great games to take the second set.
“I saw that Carlos was a little hesitant at the back of the field and I took my chances, started to feel better and move better.
“When the meds wear off, I'll see what the reality is like tomorrow morning. But right now I'm just going to try to be in the moment and enjoy this win.”
Both took some time to adjust to competing in the cold, windy conditions.
Despite one incredible volley winner, Alcaraz lost serve in the second game amid a flurry of errors, only to make a straight return, hitting a backhand winner down the line.
The competition then proceeded routinely until the ninth game when, after a long rally at 15-15, Djokovic crouched down, twitching, and slightly shook his head towards his box.
He managed to save two break points but not the third and was quickly taken off the court for a medical time-out.
He returned with a visible strap on his left thigh and Alcaraz served out the set, but Djokovic showed positive signs early in the second, taking the fight to his young opponent and opening up a 3-0 lead.
It was a tight contest, with a few moments of brilliance from both sides, but plenty of mistakes, and Alcaraz came back to tie the match while Djokovic limped around the court.
But the Serb won the title here on more than one occasion despite being physically compromised and produced a superb return game to break serve again and take the set.
Djokovic found the right groove in his groundstrokes, and especially in the return, putting pressure on an increasingly frustrated Alcaraz.
He broke at 2-3 only to break back, but the Spaniard shouted at himself again as Djokovic broke for the third consecutive time, sending a forehand arrow into the corner and then putting a finger to his ear as he soaked up the cheers.
The 37-year-old remained remarkably calm but once again conducted his orchestra after coming from 0-30 down to take the set.
Alcaraz ran out of ideas and another break early in the fourth pushed him closer to the exit, but, on the ropes, the Spaniard fought back.
A pulsating 33-shot rally that left both men barely standing helped him save a virtual match point at 2-4 15-40, but Alcaraz could not break Djokovic's serve and the 37-year-old roared with delight after the Spaniard's final backhand hit the net.
'Phenomenal performance by Djokovic'
Tim Henman, speaking to Eurosport:
“Absolutely phenomenal performance! After losing the first set he really looked down and out – he was struggling with an injury but as the match went on he got stronger and stronger.
“The quality of both players was exceptional.
“Djokovic really showed his experience. I think a lot of people, if they were dealing with an injury, would be distracted.
“But he was actually clear in his mind about the way he needed to play, which was even more aggressive – he was still counting down the unforced error.
“He was the better player that night.”
Earlier, Zverev reached his third Australian Open semi-final with a four-set win over American Tommy Paul.
The second seed, who is bidding for a first Grand Slam title, lost both of his previous two matches against the Pole, but proved stronger in the big moments and won 7-6 (7-1) 7-6 (7-0) 2 -6 6 -1.
Paul, the 12th seed, served in both the first and second sets, but Zverev fought back at every opportunity and played two excellent tiebreaks.
“I feel like I kind of stole both of those sets because he played better than me,” Zverev said.
“I played pretty well in the tiebreak. Maybe he missed a little more than he should have. I'm happy to win in four sets because it was a tough one.”
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