Thompson is excited by the chance to spoil Hawke's Bay's party.
"I know a lot of friends ...will be there, so I'm just keen to play in front of them," he said.
"A few of my close bros have been saying they're going to be supporting Wellington."
Even though he lived in Hawke's Bay from the age of 5 right through to his final year at Napier Boys' High School in 2018, for some reason Thompson never quite converted to being a Magpies fan: "I went to some Magpies games and stuff, but when I was growing up I never had like a favourite team or anything like that."
He's out for a bit of revenge on Sunday on a personal level as well, given he'll be up against some old high school rivals in the Magpies side.
Kianu Kereru-Symes, Devan Flanders, Folau Fakatava, Lincoln McClutchie and Danny Toala were all part of the Hastings Boys' High School 1st XV that were national champions in 2017.
Thompson's Napier team was never quite able to get one up over those players, although he did captain the Sky Blues to a win over Hastings and the national secondary school final in 2018, after the Hastings' quintet had finished high school.
"I'll be looking forward to playing them," he said.