'Inevitable': Ash Barty's brutal return before blockbuster showdown

Ash Barty has won her second round match at the Southern & Western Open to set up a blockbuster showdown against Victoria Azarenka in Cincinnati.

Barty was playing her first event after falling in the early stages of her Olympics gold medal bid in Tokyo.

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Barty admitted she didn't feel "100% comfortable" in the lead up to the Cincinnati Open after she withdrew from the National Bank Open hard-court event in Montreal to give her body a rest.

But the World No.1 carved out a hard-fought win over Heather Watson 6-4, 7-6 to advance to the Third Round (bye first round).

Australia's World No.1, who hadn't played a tour match since winning Wimbledon over five weeks ago, needed to shake off some ring rust on Wednesday before finally disposing of Watson's challenge after a tough one hour 46 minute duel in the Grandstand Arena.

Barty, who showed some signs of her brilliant best even while serving up eight double faults in an uneven performance, reckoned she had to "dig deep" to finally subdue the world No.67's resistance on a hot afternoon - and she enjoyed the experience.

"Heather's an extremely tough opponent. It was always going to be an exceptionally tough match for me to find my groove and rhythm and there's a little bit of work to be done," she said on court.

"It's our career and our livelihood - but it's just a game. Sometimes you have to find a way to enjoy the fight, enjoy the battle and it was certainly one of those matches today when I had to dig deep.

"And I felt like when it really mattered, I was able to find some pretty good stuff."

Ash Barty shifts gears to advance at Cincinnati Open

Indeed, there was a certain inevitability that once Barty slipped into another gear in the decisive second set tiebreak that she would set up another demanding last-16 third round encounter on Thursday with Victoria Azarenka, who beat Alison Riske 6-2, 7-5.

Barty, who was left deeply frustrated by her shock loss in the draining heat of Tokyo to Spain's Sara Sorribes Tormo, looked hungry on another hot afternoon as she opened up in brilliant fashion, racing into a 3-0 lead.

Yet she was pegged back after dishing up five double faults in the space of two service games to help gift the Briton a route back into the set.

The Queenslander quickly regained a measure of control with a break to love but eventually laboured towards taking the opening stanza while Watson produced some gutsy tennis in repelling three set points before Barty hit a glorious forehand drive at the fourth time of asking.

The 29-year-old Watson, who'd had to win three three-setters to make it this far, continued her fine resistance in the second set, saving break points in a couple of games and taking the second stanza to a tiebreak.

But as soon as top seed Barty had earned an immediate mini-break with a cracking forehand, her 29th winner, she dictated proceedings, also hammering down her ninth ace to earn five match points, the third of which she converted for a highly satisfactory return to tour action

Fans were left thrilled with Barty's tough effort after a disappointing Olympics single's campaign.

In the big match of the day, Naomi Osaka, the No.2 seed, showed real resolve in fighting back from a set and a break down to beat US teenager Coco Gauff 4-6, 6-3, 6-4 in a terrific contest.

with AAP

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