Among those competing will be top-ranked 2020-2021 season open woolhandler and 2019 world teams champion Pagan Karauria.
She'll be trying for a three-peat in the championships' open woolhandling competition from four-time winner Joel Henare, who has travelled from Gisborne.
Te Kuiti's Keryn Herbert will be missing this year. She has been in the final five times without winning in the last decade, after claiming the title in 2010.
In this year Herbert completed 50 individual open competition wins when she claimed another North Island circuit title in Te Kuiti.
In Christchurch, she would have been chasing points in this season's South Island woolhandling circuit.
Herbert and open-class shearers Jack Fagan and James Ruki are still confined by King Country's level 3 conditions.
Fagan and Ruki both need points in the PGG Wrightson Vetmed National Shearing Circuit, of which the open heats on Friday is the third round.
Defending Corriedales champion and 2012 world champion Gavin Mutch will also be absent.
Mutch had to pull out of the Circuit before it started due to shoulder injuries.
He's now intent on recovering full fitness in time to return to his native Scotland to try to win selection again for the national team in the next World Championships at the Royal Highland Show in Edinburgh in 2023.
Geraldine shearer and 2019 world blade shearing champion Allan Oldfield, who now lives in Hutt Valley, returns to the South Island to defend the Golden Blades title he won for the first time last year.
His preparation this week included shearing alpaca.