BRISBANE, Australia - Miami champion Ashleigh Barty triumphed over Victoria Azarenka 7-6(2), 6-3 in a blockbuster second rubber to draw Australia level with Belarus after a thrillingly contested first day of their Fed Cup semifinal.

Earlier, Aryna Sabalenka had survived a gruelling two-hour, 47-minute epic against Samantha Stosur 7-5, 5-7, 6-3, a bruising battle that featured 17 breaks of serve. Stosur had served for the first set at 5-4, only for Sabalenka to reel off five consecutive games to convert her fifth set point and lead by a set and a break. But after a sequence of seven breaks in a row, it was the World No.77 who leveled the match with a strong hold at the climax of the second set.

Sabalenka had struggled with her serve to this point, having served 13 double faults in the first two sets, but the World No.10 gathered herself in the decider: after saving three break points in the first game, the 20-year-old took control, breaking Stosur in the fourth game and losing just five further points behind her delivery to score the first point for Belarus.

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Having lost to Azarenka 6-4, 6-2 in their only previous meeting in the second round of Tokyo last year, the pressure was firmly on Barty's shoulders to prevent Australia slipping to a 0-2 deficit. Indeed, the first set was a contest of the narrowest margins as both players vied for momentum: no sooner had one edged ahead than the other came up with brilliant shotmaking to pull back, and neither could afford to let up for a second.

Each of the first six games featured at least one break point, but a sequence of four consecutive breaks still hadn't separated the pair. The Barty running forehand and a delectable flicked backhand slice winner down the line at full stretch had been highlights, but Azarenka - back in Fed Cup action for the first time since 2016 - had responded with some muscular backhands and efficient net play to level at 4-4.

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Leading 5-4, Barty backed off just a tad, and staring down the barrel of three break points at 5-5 it seemed as though the World No.9 would pay the price for her passivity. But the Australian caught herself, upped the aggression with her forehand to save all three and hold, and ultimately stormed through the final seven points of the tiebreak from 0-2 down to move ahead, serving her third ace en route. Azarenka, for her part, did not help her cause with her third double fault and a smash that bounced out on Barty's first set point.

The World No.61 spent the second set valiantly clinging on to the scoreboard as Barty threatened to run rampant. The Zhuhai and Miami champion broke for 3-2 with an exquisite dropshot, but was pegged back as Azarenka found some joy in pinning Barty to her backhand corner.

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But the 29-year-old's serve continued to cause her woes, and a fifth double fault handed the break right back to Barty. Swinging freely on her forehand and coming up with a few more moments of magic in the final game, the 22-year-old extended her winning streak to seven on her third match point as an Azarenka forehand found the net.