Roger Federer is through to the fourth round of the Australian Open after a dramatic five-set win over Australian John Millman. An off-colour Federer struggled to find his best form throughout the late-night match on Rod Laver Arena, making repeated errors, particularly on a misfiring forehand side. But he found his quality when it really mattered, winning six points in a row to come from 8-4 down and win the decisive fifth-set tiebreak. Millman took the first set in-front of his home crowd to alert the prospect of an upset, but Federer appeared to take back control of the match when he secured the second set on a tiebreak and followed it up with a 6-4 win in the fourth. However the Aussie was not beaten and took it to a decider. And as the clock ticked beyond midnight the fifth and final set inched towards a nerve-wracking tiebreak. Millman opened up a big lead in the tiebreak, but the nerves started to show and Federer showed remarkable fortitude to win six points on the bounce including his first match point to seal a remarkable win. "Oh god it was tough, thank god it was super tie-break otherwise I would have lost this one," Federer told Jim Courier on court afterwards. "Where to start. John played a great match… I can't even speak anymore. A great fighter a good guy and like you said it came down to the wire at the end and a bit of luck, maybe to go one way, "I had to stay so focused, make the right decision, he was doing all that stuff at the beginning he kept on coming up with the goods and I thought okay I tried I didn't do too bad and I was getting ready to explain myself in the press conference, "The demons are always there but what a match and John deserves over half of this one." Courier asked Federer how he adjusted after his opponent got off to a fast start and took the opening set. "I had to figure out a way to get him in trouble on his serve." Federer replied. "He's not known to be the best server, he's got a good serve but it's not like the tall guys coming in super fast. But he was doing such a nice job of not making too many mistakes and I was struggling in the forehands cross-court, backhands cross-court he was sort of dominating both sides. "I think for me it was a matter of holding on my own serve, figure out a way and give myself more time and chances so it was big to win that second set I thought and stretch the lead in the third. "I never really felt comfortable John did a great job of keeping me on my back foot so I couldn't really step in until the last shot I went for it, he picked the wrong side. It was tough I don't know what to say, it was really Johnny who made it so difficult for me tonight. " Federer will face Hungarian big-server Marton Fucsovics in the fourth round.