Juan Martin del Potro served notice of his strong form ahead of the Australian Open when he crushed defending champion Bernard Tomic 6-3, 6-1 in the final of the Apia International here on Saturday.

del Potro simply overpowered the talented but inconsistent Australian bringing the one-sided contest to a close with a service winner after 53 minutes.

Rohan Bopanna and Aisam-ul-haq Qureshi had to be content with a runners-up finish after losing 7-6(3), 7-6(3) to Daniel Nestor and Nenad Zimonjic.

John Isner claimed his second Heineken Open title at Auckland, hitting 23 aces on his way to a 7-6(4), 7-6(7) victory over Yen-Hsun Lu in the final. Kei Nishikori was also a winner beating world No. 7 Tomas Berdych 6-4, 7-5 to win the Kooyong Classic exhibition tournament.

The results (finals):

At Sydney: ATP Apia International: Men: Singles: Juan Martin del Potro bt Bernard Tomic 6-3, 6-1.

Doubles: Daniel Nestor & Nenad Zimonjic bt Rohan Bopanna & Aisam-ul-haq Qureshi 7-6(3), 7-6(3)

At Auckland: ATP Heineken Open: John Isner bt Lu Yen-Hsun 7-6(4), 7-6(7).

At Melbourne: Kooyong Classic: Kei Nishikori bt Tomas Berdych 6-4, 7-5.

At Hobart: WTA Hobart International: Garbine Muguruza bt Klara Zakopalova 6-4, 6-0.

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