Crosbie looks like he could be the goods after having a hand in a couple of tries, making some excellent cover tackles and linking well with his outside backs, although his methodical run up to goal kicking could be improved as he missed on the occasions that the visitors would charge.
With Crosbie's fellow Irishman Gavin Thornbury out for medical reasons, Sam Madams stepped up as the specialist lock and had a towering match on defence and turnovers, being unrecognisable by fulltime under the mud.
Caskey had his large bench come on to make a virtual all-new look team in the 48th minute, as Wanganui again closed the game out strongly with several unanswered tries after being tied 19-19 at the break.
Hawkes Bay's best period came in the second quarter after Wanganui lost double tryscorer Samu Kubunavanua when someone stood on his previously injured ankle, while young fullback Te Rangatira Waitokia was sinbinned for a foul in trying to stop a try close to the line.
The visitors were too one dimensional in the second half, whereas Wanganui worked forward off reserve halfback Lindsay Horrocks' smart kicking game.
Caked in mud himself, captain Peter Rowe was per usual happy but not satisfied.
"It's still combinations, getting to know how each other plays.
"Today we put ourselves under pressure just playing into the wind, rushing too much.
"Which is good, in a way. The boys are eager."
Caskey will spend this week strengthening the lines of communication between backs and forwards, as players still got isolated when they went themselves rather than showing patience.
"Had a real good start and then went off the boil a bit."
Like Rowe, Caskey was also happy with the first game effort of Crosbie.
"A couple of trainings, he's going to take a little bit to settle in."
Having an almost unprecedented Heartland buildup of four preseason matches including the Ranfurly Shield challenge, Caskey is likely to work his squad of 25-28 down to a shadow 22 for Wairarapa Bush - a tough task given many fringe players have had their moments in the last fortnight.
"It's not pleasant, but they're good decisions to have to make."
Crosbie had a brilliant start as his cross field chip found Kubunavanua leaping AFL-style to take the ball above his head and scoot over in the corner, with the Irishman then converting from the sideline.
Waitokia hit the gap to find winger Simon Dibben, and although the ball went loose, flanker Renato Tikoisolomone kept it on the toe for halfback Kane Tamou to score.
Getting straight back on attack, Wanganui worked to the line and Tamou made the inside flick pass to Kubunavanua to burrow over, although he immediately limped off.
Waitokia was then binned and Saracens' first-five Dane Snee grubber-kicked to open pasture for flanker George MacPherson to dash through and score under the posts.
Moments later, second-five Cole Eru cantered away and while winger Naua Uaisele was held over the line, No8 Lucas Goodin took the pass to dive into the corner.
Waitokia came back but got a horror bounce on a Saracens chip kick and Uaisele levelled the scores.
Horrocks came on at halftime and harnessed the wind to put Saracens back in their corners, where the forwards showed some lovely hands to put hooker Roman Tutauha over the line.
Another pop pass by reserve prop Viki Tofa saw the ball spread again and when Waitokia was dragged down, reserve flanker Jamie Hughes snatched the ball and bumped off his tackler to score.
Horrocks claimed a high kick at the 30m zone and fed reserve winger Cameron Crowley, who put on his famous step to get to the line, with the ball freed to fellow veteran back Ace Malo to force the ball at the flag.
Wanganui had enough for one more try on fulltime as Malo, centre Kaveni Dabenaise and reserve Dane Whale all linked to free up Crowley, who rushed over in the corner.
Wanganui 41 (Samu Kubunavanua 2, Kane Tamou, Roman Tutauha, Jamie Hughes, Ace Malo, Cameron Crowley tries; Steve Crosbie 3 con) bt Hawkes Bay Saracens 19 (George MacPherson, Lucas Goodin, Naua Uaisele tries; Dan Snee 2 con). HT: 19-19.