Angus Dinwiddie was a late withdrawal with injury, with Zac O'Keefe briefly in the frame but not selected, as Marr has brought back a very fit-looking Trent Hemi for the first time since 2014.
The war horse Dominic Rayner rejoins the lineup, although with his calf injury he will only be a batsman and is there more on reputation and willingness than current form.
"He's come in on the SOS call, really," said Marr of the former Wanganui captain and coach.
Returning allrounder Nick Harding will complete a rare statistic as he makes senior representative appearances for Wanganui across two cricket seasons and one rugby winter within the same calender year.
'He's still short of a run, but he got the seven-for [in club cricket]," said Marr.
The coach has also made the big call from his selection pool of two by picking Canadian allrounder Akash Gill ahead of English batsman Greg Smith, as Wanganui are only permitted one overseas-classed player this campaign.
Although Wanganui's best club and representative batsman last summer, Smith has not had the strongest start this season, while Gill is coming off a weekend where he took nine wickets across his games for St John's Tech and Emerging Wanganui.
"It's obviously not a call I would normally make, but it had to be made. I'd play them both if I could," said Marr.
"Akash is bowling with some heat and we need that in our attack, and he is an allrounder too."
All this means the coach was still scrambling yesterday to find another player to be the extra batsman or bowler/fielder, otherwise he will just take one of his young Collegiate 1st XI schoolboys to act as a specialist 12th man.
Matthew Simes can cover the wicketkeeper gloves for Grant, but again, Wanganui could be vulnerable if Manawatu can blunt their solid pace attack, because there just isn't a real spinner or even a proven slow bowler to do the donkey work in the middle of the innings.
Veteran batsman Mark Fraser is one option, although he is a very reluctant part-time bowler.
"When Wanganui has guys out it's bloody tough," said Marr.
"You got what you got. You don't have a choice.
"We've got more experience, but less flair maybe."
Manawatu have also had to ring in some changes from the side that got a first innings points win over Horowhenua Kapiti, with bowler Navin Patel joining regular captain Mitch Renwick in Nelson with the Stags this weekend.
Allrounder Tim Richards, now a veteran at age 25 with over 60 appearances, takes over as skipper and has spoken about his side not falling into the same trap as January when they were upset on first innings points by Wanganui at Victoria Park.
Richards fought in that match, taking seven wickets and scoring 20, but said his team went into the game complacent.
Again, Marr is aware that against an invigorated opponent playing at home, Wanganui must deliver across every session – especially after they let Taranaki off the hook with a couple of big partnerships while giving away cheap dismissals.
"We need bigger partnerships, guys in their 20-30's have to kick on," Marr said.
"We lost wickets after drinks breaks, after lunch breaks, and first thing the next day.
"We need to bowl less four-balls."
The game starts both days at 10.30am.
The teams are
Wanganui
Ben Smith, Thomas Walshe, Dom Rayner, Mark Fraser, Akash Gill, Simon Badger (c), Connor O'Leary, Matthew Simes, Ross Kinnerley, Nick Harding, Trent Hemi.
Manawatu
Mason Hughes, Brynn Cleaver, Henry Collier, Dave Meiring, Logan McHardy, Scott Davidson, Bevan Small, Tim Richards (c), Thomas Kuggeleijn, Dane Watson, Ray Toole, Jack Gleeson.