Melbourne, VIC, 18 January 2016 | AAP

Sam Stosur has been jolted from the Australian Open in straight sets, with the Aussie falling 6-4 7-6(6) to Czech qualifier Kristyna Pliskova.

Fourth-round finishes in 2006 and 2010 remain Stosur’s best results in her home Grand Slam.

On Monday night, Stosur fought for one hour and 43 minutes but couldn’t push the match to a third set, despite holding two set points in the 12th game of the second.

“Obviously I’m really disappointed not to get through. I was behind pretty much the whole match,” Stosur said.

“It was great I was able to turn it around (in the second set and force a tiebreak) but I stuffed it up with a couple of errors.”

Stosur was seeded 25th and fully expected to account for Pliskova.

Pliskova is ranked No.114 in the world and has played second fiddle to twin sister and world No.12 Karolina throughout her time on the WTA circuit.

“It was the biggest match of my career,” Pliskova said, admitting she was bothered by a leg injury in the contest.

Stosur started her 14th Australian Open as the top-ranked local hope in the women’s draw, as has been the case so many times.

She broke back twice in the second set, most notably when Pliskova was serving for the match at 5-4.

The comeback continued, yet after failing to convert either of her set points, Pliskova held serve to push the set to a tiebreaker.

Pliskova took control of the contest thanks to her powerful serve and fittingly it was the 23-year-old’s 10th ace that finished the match.