Unseeded Russian Anna Blinkova dumped world number three Elena Rybakina out of the Australian Open on Thursday following the longest tie-break in a singles match in Grand Slam history.

Blinkova, ranked 57, won the first set of the second-round match 6-4 and last year's finalist Rybakina hit back to win the second by the same scoreline.

But the match hinged on a breathtaking tie-break that Blinkova won 22-20, which lasted more than 31 minutes.

It surpassed the previous longest tie-break of 38 points, according to the International Tennis Federation.

The Russian served for victory in the 12th game of the deciding set, missing two match points, but that was only the start of the drama on Rod Laver Arena.

Match points came and went for both players but Rybakina finally cracked.

"I don't know what to say, it was super tough," said Blinkova. "I just tried to stay focused on every point.

"I had so many match points and I tried to be aggressive in these moments, but my hands were shaking, my legs too. I tried to be calm as far as I could and super happy to win.

"I was telling myself 'go for it'. I was also telling myself just stay solid, stay solid, solid, solid, and just putting the ball in the court, into the court, in the court, and finally it worked out.

"This day, I will remember for the rest of my life, especially on this court with this crowd. I will never forget it. It is the best day of my life so far."