Aryna Sabalenka shows off improvements to dispatch Donna Vekic at Australian Open

WATCH: In a battle of 2023's best players, Sabalenka snapped Bencic's winning streak, and is currently 18-0 in sets this season.

As Donna Vekic struck an unlucky 13th double fault, Aryna Sabalenka was surely reminded of her former self across the net.

Unfortunately for Vekic, the Old Aryna couldn’t come to the phone on Wednesday; the new and improved No. 5 seed instead presided over Rod Laver Arena when it mattered most, earning her a 6-3, 6-2 victory—her ninth in a row for 2023—over her former nemesis.

“I don’t know why, but here feels really special to be in the semifinals,” Sabalenka said on court. “It was so great to play here today. The atmosphere was unbelievable.”

Vekic boasted a near-flawless 5-1 head-to-head against the former world No. 2, winning their last two matches at the Tokyo Olympics and in San Diego just last fall.

“It’s really good that I didn’t know that!” Sabalenka said. “I knew she won the last two matches, but good that I didn’t think about 1-5 down. Now it’s 2-5, so three more to go!”

The Croat’s small margins off the ground are typically anchored by a formidable serve, a shot that never arrived. Sabalenka took full advantage and secured a fourth Grand Slam semifinal berth in one hour and 49 minutes.

Still, this week ought to be considered an unmitigated success for Vekic, a former world No. 19 who has just about cut her ranking in half as a result of this first major quarterfinal since the 2019 US Open. A combination of COVID-19 and a chronic knee injury—one that required two surgeries—left the 26-year-old businesswoman-turned-fashion designer pondering whether her pre-pandemic movement would ever return.

A strong fall swing aided by new coaching consultant Pam Shriver had lifted Vekic immeasurably through the start of 2023, helping her score a statement upset of No. 18 seed Liudmila Samsonova, survive an inspired effort from Czech teen Linda Fruhvirtova, and put her in pole position against an opponent who had only beaten her once in six previous meetings.

But apart from their meeting in SoCal last October, Vekic has largely avoided this steadily improving and presently unbeaten Sabalenka, one who has been to hell and back in the last 12 months thanks to serving woes that rendered her entirely unwatchable.

Where others have attempted to simply serve their way out of a protracted battle with the yips, Sabalenka set to work on a new motion, one even better than the one before.

Good that I didn’t think about 1-5 down. Now it’s 2-5, so three more to go! Aryna Sabalenka on her head-to-head with Vekic.

“Even when my serve was working,” she admitted after snapping Belinda Bencic’s 2023 winning streak on Monday, “it wasn't really right.”

It’s still not a perfect shot—her penchant for big risks have yielded their share of double faults—but it’s a far cry from what preceded it, and closer to what Vekic herself had to deal with as her more abbreviated technique fell apart from the outset of their quarterfinal clash.

Serving woes prevented the Croat from capitalizing on Sabalenka’s early unsteadiness and led to marathon games that, under the searing Melbourne sun, drained her physical reserves.

In a match between two of the game’s biggest hitters, Sabalenka opted for bigger targets off the ground, relying on her superior weight of shot to pressure Vekic into errors—25 to be exact.

Sabalenka, by contrast, emerged from a fifth straight match with a positive winner-to-unforced error differential—In no small part thanks to her double-fault reduction—striking 38 winners to 35 unforced errors.

She jammed Vekic off the forehand side to secure the key break of the opening set and got the service winners to set up a third set point, one she converted with a roaring forehand of her own.

Though she could still test Sabalenka on return, Vekic lacked the confidence in her arsenal to pose a consistent threat, and the 24-year-old was soon a game away from the semifinals at 5-1.

Continuing to press off the ground, Vekic held serve for the first time in the second set and had three looks at breaking Sabalenka as some suddenly unclutch serving appeared at the 11th hour. A 2/14 conversion rate proved her undoing as the Belarusian soon had match point, and a 1-2 punch got her over the finish line.

In a way, the Old Aryna and New Aryna aren't too different; there's still the awesome power, the relentless competitiveness. But everything is streamlined like never before as Sabalenka conquers one demon at a time en route to an overdue Grand Slam victory. Next on the docket: a first-ever Grand Slam final, and only surprise semifinalist Magda Linette stands in her way.

On the brink of her destiny, which Aryna shows up?