"They got through a fair bit of work yesterday too, so they'll be tired."
Looking for the converted try to deadlock the game in the second half with the wind behind them, Whanganui still rotated players around positions, including three halfbacks, so lacked for continuity at times and made some costly errors when camped in the opposition half.
"But you need game time and guys need an opportunity to have a run," said Caskey.
"Some really good stuff, the first 15-20 I thought was outstanding – the ball retention, the discipline, their handling was good.
"[Hawke's Bay] didn't have the ball, basically, for close to 20 minutes."
Going into the wind, try-scoring No 8 Semi Vodosese and centre Kameli Kuruyabaki cut imposing figures with ball in hand, while fullback Ezra Malo produced incisive darts and offloads, and speedy winger Peceli Malanicagi was a handful on his rare chances.
Flanker Kieran Hussey kept up an impressive workload while, after the momentum turned, he and hooker Dylan Gallien were solid on defence.
But Hawke's Bay eventually got some traction up the field as penalties crept into Whanganui's game and two tries in the space of five minutes shortly before the break proved decisive.
Turning to take the wind, Whanganui had the better of territory after the opening 10 minutes when Hawke's Bay pressured them but struggled to find a way through as the visitors worked their way out of the danger zone with professional ball control.
The home side wanted to make attacking penalty scrums their bread-and-butter, trying to spread quickly to dash away from Hawke's Bay's big forwards.
However, when Vodosese or veteran halfback Lindsay Horrocks reached for a clean pickup at the base, the Bay's final shunt or the spoiling hands of their reserve halfback Trent Hape occasionally caused half-a-second's hesitation or a fumble, and the impetus would be lost.
"I think, in the end, we were struggling a bit. We probably should have stayed [bound] and Lindsay cleared off the back," said Caskey.
"We were trying to play No 8 to No 9, and when you're under pressure, as soon as your No 8 takes his head out of the scrum, that's 100kg off [the push] and you're in trouble.
"It's a learning curve, that if we're losing that scrum battle a little bit like that, then No 9's got to clear from the base himself."
In some other noteworthy plays, prop Viki Tofa was a late inclusion to the starting XV and produced some nice offloads and caretaker halfback passes around the breakdown while, after playing some of the Whanganui Māori fixture, lock Josefa Rokotakala came on to make a series of strong tackles.
Flanker Ben Whale and halfback-turned-fullback Tyler Rogers-Holden worked hard to create opportunities.
Hawke's Bay Development 14 (M Tufunga, D Devine tries; J Falcon 2 con) bt Whanganui 7 (S Vodosese try; D Whale con). HT: 14-7.