We look back at some classic matches between Novak Djokovic and Roger Federer ahead of their Australian Open showdown on Thursday in Melbourne.
Here are some of the most memorable encounters between the two greats...
Wimbledon, 2019 Final - Djokovic won 7-6 (7-5) 1-6 7-6 (7-4) 4-6 13-12 (7-3)
This was arguably the greatest meeting between the two old foes and it came two years after their last Grand Slam clash in the semi-finals of the Australian Open - a match which the Serb won in four sets. Federer, who at 37 was chasing a record-equalling ninth Wimbledon singles title looked to have it in the bag, but Djokovic had other ideas when he saved two championship points before retaining his title in the new tie-break after four hours and 57 minutes.
US Open, 2015 Final - Djokovic won 6-4 5-7 6-4 6-4
Top-ranked Djokovic vanquished long-time rival Federer and a hostile home crowd to clinch his 10th major title with a four-set victory at the US Open. Federer had been back to his dazzling best at Flushing Meadows and enjoyed the almost complete backing of the American support, but Djokovic showed his iron-will again.
Wimbledon, 2014, Final - Djokovic won 6-7 (7-9) 6-4 7-6 5-7 6-4
This was the second Grand Slam final between the pair and what a match it was. Two tie-breaks in the opening three sets help show just how tight the contest was, although when the Serb opened a 5-2 lead in the fourth the Swiss' dreams of an 18th Grand Slam title looked dead in the water. But he saved championship point as Djokovic wobbled, losing five games in a row as the Centre Court crowd were whipped into a frenzy by their hero's comeback.
The drama continued as the set progressed. Federer sailed close to the wind when saving three break points at 3-4 but finally cracked in his next service game, Djokovic winning the title for a second time and regaining the world No 1 spot in the process.
US Open, 2011, Semi-Finals - Djokovic won 6-7 (7-9) 4-6 6-3 6-2 7-5
Talk about history repeating itself. Twelve months on from their thriller in New York, Djokovic again saved two match points - this time with Federer serving - with his go-for-broke, nothing-to-lose attitude reaping dividends once more. Having trailed by two sets to love, the Serb stormed back into the match only to fall a break down in the decider as Federer found a second wind. But with Federer serving for the match at 40-15 it all went wrong.
The match is best remembered for the first of those match points, Djokovic unleashing on a forehand return which he powered cross-court for a clean winner. He raised his arms in celebration, whipping the crowd into a frenzy. The second match point was saved too and the tide quickly turned. Minutes later he was again celebrating a remarkable victory.
French Open, 2011, Semi-Finals - Federer won 7-6 (7-5) 6-3 3-6 7-6 (7-5)
Djokovic came into this match - played in early June - unbeaten for the season. His remarkable winning run stood at 43 and few expected it to end at the hands of Federer, who was beginning to be labelled yesterday's man. But Federer rolled back the years. Not only did he fend off Djokovic with a fine serving display but, more surprisingly, he more than held his own from the back of the court and celebrated the win by wagging a single finger in the air.
US Open, 2010, Semi-Finals - Djokovic won 5-7 6-1 5-7 6-2 7-5
The Serb won a see-saw encounter in New York to deny Federer what would have been a seventh successive final appearance at Flushing Meadows. Djokovic did so by saving two match points in the final set, coming from 15-40 down to level with some nerveless play. Federer had beaten him in the tournament in each of the three previous years.
"To be honest I was just closing my eyes and hitting forehands as fast as I can on the match points," said Djokovic afterwards. "If it goes in, it goes in. If it goes out, you know, another loss to Federer in the US Open. I managed to come back. I was very lucky."
US Open, 2009, Semi-Finals - Federer won 7-6 (7-3) 7-5 7-5
This isn't the greatest match Federer and Djokovic have ever produced but it is one of the most memorable. The reason being it featured one of the all-time great shots by the Swiss maestro. Having played some superb tennis to fend off a fine effort from his opponent, Federer hit a simply stunning through-the-legs winner - a hot dog, tweener, call it what you like - to bring up match points. Djokovic grinned wryly. What else could he do against such brilliance? Federer wrapped up victory moments later and then described his shot as "the greatest I ever hit in my life".
US Open, 2007, Final - Federer won 7-6 (7-4) 7-6 (7-2) 6-4
Djokovic had defeated Federer for the first time in his career in the Montreal Masters final just weeks before the US Open and in New York he was making his first appearance in a final at the majors. But Federer swept to his fourth successive US Open crown, the first man to do so since Bill Tilden 80 years earlier.
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