Smyth had initially been hesitant as he and his wife have a young child and she is required to be on-call during weekends as a hospital radiographer.
But the couple will try to make the weekend schedules work and Caskey wanted the 1.96m tall Smyth, a regular from 2007-12 and the 2011 Heartland Player of the Year, because of his familiarity with the team's other veterans.
"He knows half the forward pack at least, played a lot with Peter [Rowe], Fraser Hammond, Baldy [Cole Baldwin]."
While the injury report is promising on prop Brett Turner's ribs, possibly returning next week, Fitzgerald is more uncertain because while a doctor told Caskey he could be available in two-three weeks, the coach would not want the 23-year-old to gamble his playing future on a shoulder that has already been reconstructed.
"I'd love him to be right in three weeks, but if we get him back later in the year, I'm only too happy. He's a young man so he's got to look after himself."
Although schoolboy Stephen Perofeta is unavailable this weekend, the team is back to their first-stringers as Hawke's Bay fullback Trinity Spooner-Neera has recovered from his rolled ankle and Ace Malo joins the reserves bench.
While Caskey admits Malo will be short of a run after eight weeks out, the 64-game veteran utility player has been doing as much as he can at training.
Loose forward Bryn Hudson is also ready to go on the bench, while after two tries for the Development team, William Short takes over the reserve halfback spot for Kane Tamou.
Caskey said this was not a reflection on Tamou, who scored the key try against Horowhenua Kapiti, but Short's passing game would be more effective against Mid Canterbury than Tamou's darting runs.
"It's probably only going to come down to horses for courses."
The other change is winger Michael Nabuliwaqe, who set up Tamou's try. He replaces Simon Dibben in the starting line-up.
Wanganui must be wary tomorrow of staying on the good side of referee Alistair Payne, as Caskey feel Mid Canterbury can be a two-three try team yet have a very good goal kicker in former Chiefs player Murray Williams.
In Ashburton last year, Williams popped over six penalties - the telling difference in Wanganui's 30-14 loss.
"Discipline's always going to be a key against them," Caskey said. "I don't think there'll be much in it, wherever we can score points [we will].
"One of our team goals is to be more miserly than what we gave away against Horowhenua Kapiti. We were pretty disappointed."
Mid Canterbury winger Ashton Tuck grabbed two tries in his team's opening 34-17 win over South Canterbury, while NZ Heartland player Jon Dampney is also to be respected in the loose forwards.
-The curtain-raiser at Cooks Gardens will be Wanganui Development against the Wanganui Centurions Under 21s.
Kickoff for the main game is 2.30pm.
