Mirra Andreeva plays a forehand return to Ons Jabeur during their second round match at the Australian Open at Melbourne Park. AP

The Russian underlined her huge potential by crushing sixth seed Ons Jabeur in under an hour in round two and followed up by showcasing her gritty fighting spirit to overcome France's Diane Parry 1-6, 6-1, 7-6 (10/5).

Down 5-1 in the deciding set, Andreeva reeled off five games in a row to leave her in a position to serve for the match at 6-5.

Parry, herself only 21, halted the surge by breaking to set up a tie-break. But the young Russian had all the momentum and imposed herself again for a remarkable victory.

Mirra Andreeva celebrates after victory against France's Diane Parry during their women's singles match. AFP

She will next meet Czech ninth seed Barbora Krejcikova or Australian qualifier Storm Hunter.

Five-time Australian Open finalist Murray was watching on television. "Andreeva down 5-1 in third," he wrote on social media. "Commentator: 'she really needs to work on mental side of her game. She's too hard on herself when she's losing'. 30 minutes later 7-6 Andreeva wins."

"Maybe the reason she turned the match around is because of her mental strength," he said. "Maybe she turned the match around because she is hard on herself and demands more of herself when she's losing/playing badly? Winner."

Andreeva, who caught the eye in reaching the fourth round at Wimbledon last year as a qualifier, said she was honoured that Murray was taking notice.

"Honestly, I didn't really think that he would watch a match, then after he would tweet, he would comment something," she said. "Honestly, I will try to print it out somehow. I don't know, I will put it in a frame. I will bring it everywhere with me. I will maybe put it on the wall so I can see it every day."

Andreeva was out of sorts in the opening set, broken twice by Parry, who returned well and dominated from the baseline.

It was a different story in set two, with the Russian breaking in the fourth game with a passing shot before consolidating and breaking again on the way to levelling the match. But Parry was unfazed and regained the upper hand with a break for 2-0 in the deciding set after a draining 16-shot rally.

She kept her cool to hold on through a 14-point third game and opened up a 5-1 advantage, seemingly destined for victory, only for Andreeva to surge back.

"I don't know, just the adrenaline, the desire, the feeling that I want to win," she said of he comeback. "It was a tough match. She played really well in the first set. It was really tough for me to do something. Then I just found my way. Honestly, overall it was a crazy match for me."