The Brit had reached the semi finals and quarter finals on her previous two visits to the Aussie Open, losing each time to the eventual victor. "I don't feel by any means that it's a massive catastrophe".
Pera's return was surprisingly effective against the Konta serve, and she forced seventeen break points in all against just two for her opponent. "I think you can count on one hand how many ideal matches you have".
"I didn't play well enough to be able to kind of earn that third set and try to earn my way out of the match".
However, the 26-year-old Brit slipped over to be broken after a disastrous service game and Pera made no mistake in seeing it out this time.
Konta fell over twice during the match and said afterwards: "I do think I was a little uncoordinated today".
The upset result came in Pera's first appearance in the main draw of a grand slam, a spot she claimed when Russia's Margarita Gasparyan withdrew after qualifying. In the opening set she was not afraid to hit out, often gaining impressively consistent depth on her shots.
She made a poor start against Pera but would have been confident of wresting back control of the match in the second set after breaking the American on a double fault for 2-0.
In constant trouble on her serve, Konta went 3-4 down in the second set when she left too little margin for error on mid court backhand and put it wide on a fourth break point.
The third seed, whose preparation was hampered by a thigh injury, was always trailing against the world number 88 before being edged out 7-6 (7/1), 6-4 in one hour and 59 minutes on Rod Laver Arena.
The British No 1 got her to 30-30 in the next game but that was answered with two straight aces.
This time Pera finished the job, sealing victory on her fifth match point when Konta framed a smash that sailed away into the stands.