The remainder of the second round was played out on day four of the Australian Open. And with it came the upset of not just this tournament, but in recent memory as Denis Istomin eliminated Novak Djokovic 7-6, 5-7, 2-6, 7-6, 6-4.

The signs were on the wall early as Djokovic found himself in an early hole dropping serve to the veteran in the first set. But the Serb fought back to send the set to a tiebreak. There, it was Istomin who took his play to another level and gained a one-set advantage.

The hole nearly became deeper as Djokovic found himself facing two set points serving at 4-5 in the second set. However, his serve pulled him through and he evened the set and parlayed the momentum into a quick break of service. He would close out the set on his serve and even the match.

Djokovic would ride the wave of momentum in the third set winning with ease but just as it appeared he would take the match home, Istomin broke serve early in the fourth. However, Djokovic struck back once more and another tiebreak ensued. But playing the match of his career, Istomin summoned up clutch shots and capped off the breaker with an ace, forcing a deciding fifth set.

In the fifth, it was Istomin who drew first blood with a service break to gain a 3-2 advantage. And displaying remarkable calm, poise, and focus, he closed out the match strong without allowing the 6-time Australian Open champion an opening.

It was easily the best match of the tournament and was certainly unexpected as Istomin came into Melbourne as a wild card, ranked world no. 117. The epic five-setter took four hours and 48 minutes to decide the outcome.

Istomin was nearly at a loss for words afterwards, “I surprised myself. I want to thank my team and my mum – they do a great job.”

Djokovic gave credit to his opponent afterward and was undecided as to his future schedule. His immediate focus was to go home and spend time with his family.

Earlier on Thursday, 5th-seeded Karolina Pliskova wasted little time in a 6-0, 6-2 win against Anna Blinkova of Russia in the women’s draw.

The Czech overpowered the 19-year old winning 86 percent of her first serve points. She fired 9 aces and struck 24 winners to just 13 unforced errors. Blinkova placed just 34 percent of her first serves in play.

“I’ve improved a little bit since the first round,” she said. “It’s always good to be in the zone.”

Pliskova has dropped just two sets in her two rounds in Melbourne.

In other action, third-seeded Milos Raonic advanced to the third round with a 6-3, 6-4, 7-6(4) win over Gilles Muller. He would need just less than two hours to advance.

” I played well, I was efficient,” said Raonic. “I got the breaks and I faced some scares. I played well in those situations and I stepped up at the end of that third set. He stepped up, as well. I'm happy I was able to finish it out there.”

Next up for the Canadian is veteran Gilles Simon.