ROME, Italy – WTA World No.4 Kiki Bertens showed both spirit and quality to overcome lucky loser Amanda Anisimova, 6-2, 4-6, 7-5 at the Internazionali BNL d'Italia.

Coming off the back of a win in Madrid last week, as well as a trip to the semifinals of Stuttgart at the end of April, the in-form Dutchwoman had to dig deep to overcome one of the WTA Tour’s up-and-coming stars.

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Fatigue and the effects of the Rome surface, considerably slower than in the Spanish capital, particularly in the wake of Wednesday’s persistent rain, worked against Bertens, who showed her mental toughness to win through.

It was the 27-year-old’s eighth win in succession, although her streak of successive sets won was ended at 13 by the American.

Bertens, seeded No.6 for this event, ultimately eased to the opener, but she did not have it all her own way, facing three break points over its duration against an opponent that she had never previously met.

For a significant period in the second, it seemed that Bertens might run away with the match as she rapidly moved to establish a double-break advantage over the teenager.

Anisimova, who had defeated Elisabetta Cocciaretto in the first round after losing out to Kristina Mladenovic in qualifying, showed mental resilience beyond her years and profited from a dip in her opponents’ delivery in the second set. 

Bertens complained to coach Raemon Sluiter at a changeover that she felt her shots had “zero power”, and for a half-hour period she failed to hit through her opponent, who enjoyed a spell in which she never seemed to miss a ball.

On the other side of the net, Bertens delivered three double faults as she lost six games out of seven to be pushed into an unwelcome decider given the volume of tennis she has played in recent weeks.

The third set proved to be an incredible game of cat and mouse, in which a hold of serve proved every bit as valuable as a break.

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Three times Bertens edged ahead by winning on her opponent’s delivery, yet on each occasion the WTA World No.54 was able to strike back immediately. 

As the match reached its climax, the players exchanged some delicious winners. Anisimova delivered a cute drop shot to edge ahead in the 11th game only to be countered by some outstanding defense from Bertens, who robbed her opponent of a winner and struck one of her own in a brilliant single stroke. 

This act of defiance proved to be decisive as Anisimova leaked three successive errors to give up the game. 

With the scent of victory, Bertens was able to stave off another reply from her opponent, who got as close as 30-30 but ultimately could not shackle the power of the Dutchwoman.

After delivering the winning blow, an ace down the tee, Bertens let out a primal roar of defiance that encapsulated the hard work and determination that had gone into a victory that required over two hours to achieve. 

She will be back on court later on Thursday to face Alizé Cornet or Carla Suárez Navarro in what promises to be another immense test of willpower.