Azarenka pushed by Niculescu in opening match

MELBOURNE, Australia (AP) -- Victoria Azarenka has opened the defense of her Australian Open title with a 6-1, 6-4 win over Monica Niculescu of Romania.

Azarenka powered to a 4-0 lead in the opening set over Niculescu, who is winless in singles tournaments on the WTA Tour.

The top-seeded Azarenka was down a service break and trailed 3-0 in the second set before coming back to level the set at 4. She then broke Niculescu's serve in the ninth game before serving out Tuesday's match.

Azarenka could meet No. 3 Serena Williams, who also won Tuesday, in the semifinals at Melbourne Park.

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