"We weren't expecting that until we got there," said Wanganui manager Kellie Watkin.
Wanganui gamely held their strengthened opposition to 0-0 until 15 minutes to go, when Hawkes Bays' coach and former leading Black Stick Caryn Paewai injected herself into the match at the crucial point.
"One of our girls got a green card and they went from there," said Watkin.
The floodgates opened as the 1-0 scoreline blew out with four more goals to the home team.
Wanganui men were already 5-0 down by halftime of their clash and efforts to concentrate solely on defence didn't pan out either as seven more goals were slammed home in the second stanza.
Disappointed coach Langley Atkinson said the Hawkes Bay players not having Saturday club games proved telling.
"We were run into the ground.
"You could see the team was looking jaded and tired, and Hawkes Bay were just humming along."
Wanganui had been a little makeshift with new Junior Black Stick training squad member Martin Atkinson not playing, while Kane Watkin was sore after club play followed on from the national under-21 tournament.
Both Wanganui teams will now go into the Central Hockey League playoff for third/fourth this Sunday.
RESULTS: Manawatu Club Competition Men: TCOB drew with Massey 3-3; Rangers lost to MCOB 5-1. Women: TCOB women beat HSHC Evergreens 4-2; Collegians lost to HSHC 4-0. Central Hockey League Men: Wanganui lost to Hawkes Bay 12-0. Women: Wanganui lost to Hawkes Bay 5-0.