MELBOURNE: Unseeded Maria Sharapova showed she is a serious contender for this year's Australian Open as she destroyed 14th seed Anastasija Sevastova 6-1, 7-6 (7/4) on Thursday.

Against an opponent who had thwarted the Russian's Grand Slam comeback in the last 16 of the US Open last year, Sharapova sped through a scintillating first set in 23 power-packed minutes.

She wobbled when serving for the match but came through a tiebreak to set up a potential third-round clash against in-form 2016 Australian Open champion Angelique Kerber, who plays Donna Vekic later.

"When she broke back I thought: 'Oh, it's going to be three sets again," said Sharapova, who added. "At the US Open she was fresher."

Sharapova, back in the top 50 after a 15-month ban for taking the performance-enhancing substance meldonium in Australia in 2016, demonstrated all the shot-making that made her a five-time major winner.

In a hopelessly one-sided first set, the world number 48 powered home 12 winners, was successful on all six occasions she approached the net, smashed down two aces and lost just nine points.

"I knew I had to get a good start and I'm happy to get through on a day like this," she said after the 1hr 20min match.

As temperatures soared towards 40 Celsius (104 Farenheit) on the hottest day of the tournament so far, it was a sizzling demolition of an opponent who had taken the Russian to three sets in both their previous meetings.

Sharapova needed more than three hours to avenge her US Open defeat to Sevastova when the pair last met in Beijing four months ago and was in no mood to take her time again as the mercury rose.

When she broke Sevastova to open the second set it looked like an early ice bath was in order. But the Latvian, who reached back-to-back quarter-finals at the US Open in 2016 and 2017, suddenly woke up against the 2008 Australian Open winner and broke back immediately.

The jolt to the Sharapova juggernaut was evident and she began to make unforced errors as service holds and breaks were exchanged.

At 4-4 a backhand winner got Sharapova to break point and when a second screamer followed it was greeted by a double-fist pump from the Russian.  But still Sevastova was not done and broke back again to force a tiebreak.

Sharapova regathered and was not to be denied as she hit a scarcely believable forehand crosscourt winner on the run to get to 5-2.

She still managed to squander a pair of match points before getting over the line.

Sharapova, one of the highest earners in women's sport, suffered a string of early defeats after her comeback but has been working her way back up the rankings since.

She broke through to win the Tianjin Open in October -- her first title since 2015 -- and enjoyed a run to the semi-final in Shenzhen to start the year.  –AFP