Novak Djokovic is through to the final of the Australian Open but the world number one was made to work hard for his 6-3 3-6 6-7 6-1 6-5 victory by Andy Murray.
The world number one started off the stronger of the two players, with the Serbian star taking the first set by breaking Murray's serve, which looked shaky in the opening stages.
However the Scot managed to battle back as he found his way into the game and took the second set to level matters against the top seed at Melbourne Park.
Murray then continued to grow and took the third set, before a Djokovic fightback meant it was the Serb who sealed the win in four hours 50 minutes.
Defending champion Djokovic was pleased with the win and is now looking forward to taking on Rafael Nadal in the final on Sunday.
"I'm, extremely delighted to be in another final," Djokovic said. "It was a physical match, almost five hours.
"Andy deserves credit for coming back into it. He was fighting and I was fighting.
"It was one of the best matches I've played."
Djokovic had two break points as early as Murray's first service game and a double fault from the Scot resulted in the top seed taking a 3-1 lead.
Murray appeared to be struggling but he did manage to break Djokovic only for the Serb to hit back before seeing out the set. The second started in a similar fashion with Djokovic moving 2-0 up.
However, he was denied a double-break and soon Murray was back in it as he broke his opponent and then held his serve to draw level. Having found his feet Murray made Djokovic pay for some uncharacteristic errors and forced the break to go 4-2 clear.
Despite Djokovic's best efforts, Murray stayed focused to claim the set and level the match.
A gruelling third set followed in which they exchanged breaks and several missed opportunities meant a tie-break, which Murray took with little resistance from the Serb.
The fourth set proved to be rather one-sided as Djokovic raced into a 4-0 lead before taking it 6-1.
Djokovic had looked tired in the earlier sets but suddenly he was full of energy and he broke twice to edge closer to the victory. At 2-5 down Murray was staring defeat in the face but he produced some superb tennis to break and before long the set was level.
However, Murray could not keep up the momentum as Djokovic saved three break points and then broke to complete a memorable victory.