A what? A spinner? No way?
Isn't it a rite of passage for speed merchants such as Adam Milne, Dougie Bracewell and Ben Wheeler?
"I was trying to put too much spin on it," he says with a laugh. "I guess these things happen."
On reflection, it is plausible that Kain can put his internal oblique muscles out of kilter. His bowling action must make chiropractors wince.
After all, India batsman Yuvraj Singh did once describe Kain's action, in his vernacular (Hindustani), as bowling like a "dying worm".
The lanky bowler jogs up from behind the umpire, puts himself almost in a pause, akin to a TV freeze frame, before launching the white ball in a sling-like fashion by carrying his body weight on the back foot in preying mantis fashion.
The left-armer finds the self-assessed "frog-in-the-blender" routine natural, almost suggesting the sense of unorthodox action is in the eye of the beholder.
He has defied suggestions from coaches over the years to land on his front foot for more momentum, for fear of upsetting his rhythm.
The most economical CD Twenty20 bowler last summer says he did his best to return for this summer's Georgie Pie Super Smash but it was an ill-timed move.
"I came back too soon and re-tweaked it," he says, revealing he had played a few games with The Station Napier Old Boys' Marist (NOBM).
He lauds fellow spinner Ajaz Patel for "doing a great job" but accepts he had a tough time watching CD play on TV from the comfort of his lounge.
"Hopefully it'll be my last injury of the season," he says, revealing he has been playing for his Nelson club team.
He is aware NOBM have qualified for the CD region stage of the New Zealand Club Championship and hopes to go with them to Auckland should they progress that far come April next year.
While the white-ball campaign didn't start well for the Kruger van Wyk-skippered Stags, Kain believes they'll do better than last season.
"The boys are doing well. Three out of 10 wins in the T20s aren't great but we're improving and doing well in the four-dayers [Plunket Shield]."
He feels CD have a capable team on paper so if they play to their potential then they will savour the joys of winning the Ford Trophy at Pukekura Park in 2011-12.
It's imperative CD win their first three games, he says, mindful it is similar to T20.
Stemming the flow of runs on a compact but picturesque park is the key.
Field placements - with two players allowed outside the field restrictions in the first 10 overs and four for the rest of the game - will mean opening seamers must take wickets.
"Some days you'll bowl well and go for runs but it's important to take wickets because if the batsmen settle in then it'll become hard work," he says.
Black Caps Bracewell and Milne will play sporadically because of international duties but Kain emphasises Ben Wheeler and swing bowler Seth Rance have been outstanding.
"I'm certainly glad Milney's in our team," he says of the strike bowler who is flirting with the 150kmh mark since his tour of the United Arab Emirates in the past few weeks.
Veteran opening batsman Jamie How will retire after the trophy season ends in February.
