"The boys played with that much heart and conviction," said Tucker.
"We didn't die wondering. Very proud of the boys. We're only going to get stronger from it."
Tucker said prop Gabriel Hakaraia had an awesome match, leading from the front, while his Steelform Wanganui team mate Dane Whale had a couple of nice touches from first-five.
Reserve first-five Josh Fifita came on in the second half and combined well with second-five Ethan Robinson during Whanganui's comeback.
Despite the disappointment of losing the shield they won last year, Tucker agreed local Maori rugby has continued to strengthen alongside their bigger provincial neighbours, recalling trips to New Plymouth in previous years when the side was badly beaten.
The side will re-group at Thursday training to prepare for their final game against Manawatu Maori in the Cooks Gardens curtain-raiser on Saturday
"These boys are as keen as, they're hurting from this and there's a new shield up for grabs," said Tucker.