Magnificent Ko roars into Tour Championship lead

World number one Lydia Ko fired a sensational course record 10-under-par 62 to power into the lead at the LPGA Tour Championship on Friday.

The teenager from New Zealand blasted 11 birdies on her way to taming the 6,450-yard layout at the Tiburon Golf Club in Naples, Florida.

It was an extraordinary performance from the 19-year-old, whose round might have been better had it not been for a bogey on the par-three 12th.

The New Zealander needed only 22 putts to compile her round, which followed a first round 70 on Thursday which saw her start the day at two under.

By the time Ko headed to the clubhouse she was sitting on 12 under, a 36-hole aggregate of 132.

With the round still in full swing, Ko was five shots clear of her nearest rivals in the clubhouse, Jessica Korda and Mariajo Uribe, who were both at seven under.

Ko's round leaves her firmly on target to claim victory in the season-ending $2million tournament.

A win this weekend would also see her clinch the CME Globe title, the LPGA Tour's points race, which would earn her another $1 million bonus.

Her two closest rivals in the points race -- which Ko has won for the past two seasons -- finished the second round well down the leaderboard.

Thailand's Ariya Jutanugarn, the CME Globe points leader, is eight shots off the lead after a four-under-par second round 68.

Canadian teenager Brooke Henderson meanwhile was unable to improve on her level par first round, firing another 72 to remain at even, 12 shots adrift of Ko.