Australia is one step closer to a drought-breaking Fed Cup triumph after Casey Dellacqua had "the best birthday I could have asked for".
Dellacqua and Ash Barty combined to lead Australia to a 3-2 victory in a World Group II Fed Cup tie against the Ukraine in front of 3108 at the Canberra Tennis Centre on Sunday.
The pair outclassed Ukrainian twins Nadiia and Lyudmyla Kichenok 6-3 6-4 to send Australia to a World Group play-off on April 21-22, and celebrate Dellacqua's 33rd birthday in style.
Should Australia win that, they will be promoted to the World Group for the first time since 2015 ahead of the 2019 Fed Cup.
Barty had gifted Australia a 2-1 tie lead to start the day when she beat 15-year-old sensation Marta Kostyuk but things threatened to go awry soon after.
Unranked singles player Nadiia Kichenok shocked Australian favourite Daria Gavrilova in the final reverse singles rubber, as the Ukrainian blasted 21 winners in a thrilling 4-6 6-2 6-3 win to send the tie to a doubles decider.
What's more stunning is Kichenok wasn't even slated to play Gavrilova until just before the match – Ukraine sprung a late surprise and called her in to replace her sister Lyudmyla Kichenok.
You will now receive updates fromSport Newsletter
Sport Newsletter
Get the latest news and updates emailed straight to your inbox.
But a frustrated Gavrilova had a poor weekend, and Australian No. 1 Ash Barty and doubles specialist Casey Dellacqua proved a much tougher task for the Ukrainian sisters.
The Australian duo were in command for most of the contest, with their combination looking far superior than that of the Ukrainian pairing.
Ukraine were left to rue the absence of their two best players in world No. 3 Elina Svitolina and No. 40 Lesia Tsurenko.
Ukrainian captain Mikhail Filima's decision to switch players for Sunday's final reverse singles rubber came as a shock given world No. 883 Lyudmyla Kichenok pushed Barty in three sets on Saturday.
But the late ring-in still had Gavrilova's number as the Australian failed to bounce back from her opening day "shocker".
It took plenty of grit but Gavrilova clinched the first set before Kichenok stormed back into the contest with a dominant second set.
Gavrilova fended off two break points in the deciding set but frustrations boiled over and left her in need of a new racquet as Kichenok served to level the tie.
Barty says the Australian team didn't need to rally around Gavrilova, confident the 23-year-old would be able to find form in her second stint on court.
"Dash is Dash, she's very chipper," Barty said.
"She was disappointed, that's no secret, she was disappointed with the way things went out on court but she's also very, very good at moving on."
Ukraine's late change even caught Kostyuk by surprise before she opened the day in a straight sets loss to Australian No. 1 Barty.
"Before my match I was like 'who is playing?' Because both of them are preparing," Kostyuk said.
"Everyone was saying 'Nadiia', and I was like 'what? Why?' When we were talking [on Saturday] the plan was Nadiia was going to play. It just changed."
[contf] [contfnew] 
SYDNEY MORNING HERALD
[contfnewc] [contfnewc]
