Perth: New Zealand have been urged to unleash speed demon Lockie Ferguson against Australia, as the tourists debate whether to take a cautious approach with spearhead Trent Boult.

Boult has been battling a side strain since arriving in Australia and has barely bowled in the nets. While he has a superb record with a pink ball, with 16 wickets in two Tests, the tourists want to make sure he is also fit to play in the showcase events of Melbourne and Sydney.

As that debate continued, Ian Smith, the Black Caps' gloveman in their one and only series win on these shores more than 30 years ago, said the time had come to hand Ferguson his Test debut at Optus Stadium on Thursday.

Lockie Ferguson. Credit:Getty Images

"They've got to wake up and pull the curtains and find out where they are and that's Australia and that is conducive to bowling fast. I believe he should play. He's an element of the unknown," Smith said.