A famous calendar Grand Slam remains on the cards after Novak Djokovic produced a performance for the ages to down Alexander Zverev and reach the US Open final - and now he is ready to leave it all out on the court in the final.
The world number one again demonstrated all of his battling qualities and resilience as he recovered from a set down to overcome the German in five gruelling sets, 4-6 6-2 6-4 4-6 6-2, and secure his place in Sunday's showpiece in New York.
Having already triumphed at the Australian Open, Roland Garros and Wimbledon this year, Djokovic is just one victory away from sealing the historic feat of a calendar Grand Slam as he now prepares to face second seed Daniil Medvedev in the final.
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Some of the tennis played inside Arthur Ashe Stadium was beyond belief at times - a ludicrous 53-shot rally at a crucial point in the third set of particular note - as Zverev, the Tokyo Olympic champion, threw absolutely everything at his opponent, ultimately in vain.
Djokovic, as is usually the case, was simply too good and always managed to just about find a way to repel the fourth seed and ensure that his quest for the perfect Grand Slam season remained intact.
With Medvedev no doubt delighted the match went to five exhausting sets after he cruised past Felix Auger-Aliassime earlier in the evening, 6-4 7-5 6-2, Djokovic has vowed to treat the final as though it were the last match of his career.
"Thank you, the atmosphere was amazing - the best atmosphere of the tournament so far," Djokovic said in his on-court interview.
"These are the moments we live for, the unique opportunities we dream of every day when we wake up and are trying to find the motivation to go out and do the same things over again.
There is only one more match. All in, all in. Let's do it! I'm going to treat that match like it's the last match of my career.
"There is a lot of different emotions, it is kind of a hurricane of emotions, even in one point, you are by yourself on the court so you have to find a way. Over the years I have managed to find a formula that works for me, many things combined. Tennis is very beautiful but demanding."

Novak Djokovic gaat zondag op voor zijn 21e Slam

Image credit: Getty Images

All the attention will no doubt be on the Serb to see if he can clinch his 21st Grand Slam title, move beyond rivals Roger Federer and Rafael Nadal and seal the clean sweep of majors for the season, but Medvedev may yet have something to say about it.
While Djokovic's pursuit of yet another historic achievement has appeared somewhat inevitable at Flushing Meadows, this has been a tournament of wild matches and unpredictable results. Could there be one more surprise on Sunday?
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