Gatland will be playing against his old province, for whom he made one appearance in 2015. That's not the reason he's starting, says Jackson, more the fact he offered a calm head in the second spell last week.
Rather than seeing Parsons' promotion as a nuisance to his side's momentum, Jackson was thrilled for his captain, who should be back for next week's clash with Wellington, as the All Blacks have a bye.
"We're over the moon for him. He works tirelessly in our environment and at the Blues. He'll run over broken glass for that team and he sends his best wishes to our boys," says Jackson.
The coach has had some telling recent Shield experiences in Napier. In 2013 he helped guide Counties Manukau to their first ever success in downing Hawke's Bay and then last season Harbour scored a rare five tries in a 48-32 Shield defeat against the Magpies. The attacking mindset they adopted in that second stanza will again be imperative tomorrow.
"You embrace the Shield. It's quite exciting. Some of these guys have never challenged for it. You have to attack it, though. If you hold back, you are in trouble because the team at home grows another arm and leg," declares Jackson.
There is also the opportunity to take another Premiership scalp, and he feels they can exploit areas of Waikato weakness, though he naturally was not going to elaborate on that to the Herald.
"They'll be typical Waikato, they'll use the ball, maul, work hard around the ruck and they have some backs who can rip open a game."
So kicking poorly to them will be fraught, as will any soft defence.
Jackson is "comfortable" with where North Harbour are at with the breakdown trial laws, as they should be, with most having been familiar with them through club rugby and pre-season The variable is still referees' interpretations.
Centre Matt Vaega is forming a very useful midfield combination with Michael Little. The pair made several breaks between them against the Steelers.
Vaega will be up against his old Kelston Boys' High First XV teammate Nathaniel Apa. At school, Vaega was at No 10 and Apa at 12, but the latter will be at centre tomorrow, outside the dangerous Willis Halaholo.
"He's a big boy and got some good feet, so I will have to look after him. They've got some exacting players in the backline, but the forwards always set the platform for us. We'll look to bring the pressure defensively," Vaega says.
"We're fortunate to have another chance at the Shield this year. It doesn't come round very often.
"I can't remember the last time Harbour won a first round match, so we'll try and take that momentum in."
Waikato have made five changes, with Hurricanes' crowd favourite Loni Uhila slotting into the No 1 jersey, while No 8 Jordan Manihera starts against his old province. Jordan Trainor moves back to fullback after Shaun Stevenson suffered a knee injury against the Makos.
Waikato ended Harbour's first Shield tenure in 2007 with an emphatic 52-7 hiding in Albany, in which their All Blacks' loose trio and Stephen Donald were in imperious form. Harbour have not beaten the Mooloos since 2008.
Kickoff is at 2.35pm tomorrow.
Waikato: Jordan Trainor, Iliesa Ratuva Tavuyara, Nathaniel Apa, Willis Halaholo, Sevu Reece, Sam Christie, Isaac Boss (c), Jordan Manihera, Murray Iti, James Tucker, Brian Alainu'uese, Jacob Skeen, Atu Moli, Hame Faiva, Loni Uhila; Reserves: Steven Misa, Latu Talakai, Sefo Kautai, Whetu Douglas, Mitch Jacobson, Pele Cowley, Jason Robertson, Tevita Taufui
North Harbour: Matt Duffie, Afa Fa'atau, Matt Vaega, Michael Little, Tevita Li, Bryn Gatland, Bryn Hall, Murphy Taramai, Kane Jacobson, Chris Vui (c), Brandon Nansen, Gerard Cowley-Tuioti, Sione Mafileo, Vyron Smith, Nic Mayhew; Reserves: Kalem Chan-Boon, Adrian Smith, Karl Tuinukuafe, Connor Collett, Dylan Lam, Chris Smylie, Matt McGahan, Mark Telea
