Rafael Nadal stages dramatic comeback to send Spain through to ATP Cup final (VIDEO)

Rafael Nadal battled back from a set down to defeat Australia's Alex De Minaur in Sydney to send his Spain side through to the ATP Cup final, where he will meet old foe Novak Djokovic and his Serbia team.

World No. 1 Nadal was under pressure from the opening set as he fell behind 4-6 and was forced to claw things back to parity after fighting his way through a tight second set 7-5. Nadal then took control and showed his class as he romped to victory with a dominant final set as he claimed the decider 6-1.

De Minaur stunned the watching fans as he broke Nadal in the first game of the match, then held his nerve throughout the rest of the opening set to take a dramatic early lead.

The Australian star was dominant on his own serve, and didn't look under any threat until the second set, when Nadal finally earned his first break point on De Minaur's serve. He converted it, then went on to take the set as the momentum shifted in the Spanish star's favor.

And Nadal stamped his authority on the match in the final set as he won the first four games of the set to help close out the set, and the match.

After the match, Nadal paid tribute to his opponent, saying: "He had a lot of energy, he plays with a lot of passion, sometimes a little too much."

Spain will move on to take on Serbia in the ATP Cup final, with the world's top two players leading the way.

It means Nadal is on a collision course with longtime rival Novak Djokovic as he bids to defeat the Serbian star for the first time on a hard court since 2013.

But the Spanish star said he hasn't put together a gameplan to face Djokovic – who leads the head-to-head score between the pair, 28-26 – just yet.

"No idea yet, I'm just happy for now, tonight, to be where we are," he said.