It was far from perfect and ideal but world number one Simona Halep avoided a big scare as she outlasted local teenager Destanee Aiava 7-6 (7-5) 6-1 to reach the Australian Open second round.

The Australian Open has never been a happy hunting ground for Halep, who suffered successive first-round exits in 2016 and 2017.

And the Romanian star was facing another early elimination at Melbourne Park when 17-year-old Aiava powered her way to a 5-2 lead and a pair of set points after chest discomfort had forced her off the court for treatment.

But Halep – who rolled her left ankle in a worrying moment in the second set – dug deep to battle into the next round, though the two-time quarter-finalist appeared in discomfort between points.

Aiava looked overawed early but the powerful teenager eventually settled and reeled off three successive games for a 3-1 lead.

Halep, however, managed to stem the tide and halt the hard-hitting Australian by breaking back in the next game.

But Halep never looked comfortable, forced to rush her shots as Aiava fended off three break points to take a commanding 5-2 lead.

Just as Aiava was about to serve for the set, she required off-court treatment after complaining of chest problems.

Aiava returned to the court a shadow of herself, zapped of energy and momentum – even forgetting the score – and Halep pounced, saving two set points as she won three consecutive games to level the match.

Despite her body language fading, Aiava refused to surrender to force a tie-break but Halep's experience paid off in the opening set.

And Halep – seeking her maiden major following two runner-up trophies at the French Open – continued where she left off in the second set, despite hurting her ankle which required further strapping and saw her walk gingerly between points, as a deflated Aiava bowed out.

STATISTICAL BREAKDOWN
Halep [1] bt Alava 7-6 [7-5] 6-1

WINNERS/UNFORCED ERRORS
Halep – 20/22
Alava – 25/51

ACES/DOUBLE FAULTS
Halep – 2/1
Alava – 2/9

BREAK POINTS WON
Halep – 5/13
Alava – 3/8

FIRST SERVE PERCENTAGE
Halep – 57
Alava – 51

PERCENTAGE OF POINTS WON ON FIRST/SECOND SERVE
Halep – 63/51
Alava – 51/48

TOTAL POINTS
Halep – 84
Alava – 72