Croat Lucic-Boroni into Melbourne Park semi-finals

The 34-year-old, whose only other grand slam semi-final was against Steffi Graf at Wimbledon in 1999, will face either Britain's Johanna Konta or second seed Serena Williams, who play in the next quarter-final, for a spot in the final.

"I can't believe this, this is crazy," said Lucic-Boroni. "I can't believe I'm in semi-finals again. I feel a little bit in shock right now."

The match saw several swings of momentum with neither player really able to seize control, while Lucic-Baroni had trouble holding her serve when playing into the sun.

Pliskova took an early lead in the first set only to be pegged back by the aggressive tactics of her 34-year-old opponent, who had heavy strapping around both her left thigh and calf.

Lucic-Baroni, after sealing the first set in 32 minutes, won the opening games of the second before Pliskova broke back and then took a medical time out to fix strapping on her right foot.

The break saw the momentum shift towards the fifth-seeded Czech and she ran away with the second set.

Pliskova promptly lost serve in the opening game of the decider, but Lucic-Baroni handed the break right back after a controversial call at 15-15 when a serve was incorrectly called out resulted in a replay of the point.

Lucic-Baroni served two double faults to allow Pliskova to get back on serve.

The Croatian's problems with the ball toss at the northern end of Rod Laver Arena resurfaced and Pliskova was able to take a 4-3 lead.

Lucic-Boroni took a medical time out and from that point on had the upper hand. She won 12 of the next 13 points to storm through the last three games and into the semi-finals.

"I know this means a lot to every player to reach the semi finals. But to me this is overwhelming I will never, never forget this day and this last couple of weeks," she added.