The 30-year-old, who fashioned a distinguished career with Otago, the Blues and the Highlanders as a level-headed centre/fullback, left New Zealand in 2021 to join Welsh club Ospreys, playing 39 games for them over two seasons.
However, early last year, he tells Mountain Scene during a flying visit home, a delay in confirming player budgets caused him to look towards Japan to protect his career.
"I had a contract to stay, I definitely wanted to stay, but I guess if you look there’s a couple of English teams that have folded. There’s always talk of teams in the UK doing this.
"The whole market itself, Japan is probably the most stable, along with probably France, and you get older and you start weighing up different decisions."
Collins, however, says it wasn’t solely the financial turmoil in Wales that caused him to bail.
"Japan’s closer to home, and obviously this [past] week I’ve been lucky enough just to be able to shoot home ... Also, the opportunity to learn like a new language or a new culture is something pretty different you’re probably going to struggle to replicate outside of rugby."
Collins signed a two-year contract with Tokyo-based Toshiba Brave Lupus, which from this season has also onboarded All Black stars Richie Mo’unga and Shannon Frizell.
Though he only got onto the field once, as a sub, through their first six (unbeaten) games, he says "I sort of knew that before signing".
"We’ve obviously got some quite good foreigners and ABs, and you’re only allowed to play four foreigners at a time.
"It’s pretty cool to be able to sit back and watch [Mo’unga and Frizell] — their training abilities and performances are second to none."
As for the future, Collins says he’d be keen to stay in Japan for a while, but adds "I’d love to come back to Otago for a year at some stage".