Leach is one of the most popular players across the county circuit, with fellow players and even rival spectators – partly down to his on-field success as a classic left-arm spinner, but also because of the unassuming personality of the former Cardiff MCCU player known increasingly widely as Nut.
And for anyone involved with the Lions set-up for the last two winters, the 26-year-old’s selection is reward for the mental strength he has shown in battling back from the sort of blow that has wrecked many careers.
Leach was on a high at the end of the 2016 season, having taken 68 first-class wickets in Somerset’s thrilling late bid for the county’s first Championship title.
He was rewarded with his first Lions call-up, but in the routine testing conducted by the ECB on all players apparently on course to play international cricket, his world was turned upside down. A bowler whose action had never raised a murmur from opponents or umpires was suddenly told he had to change.
Peter Such, the ECB’s lead spin-bowling coach, was equally shocked. And there was further turmoil for Leach later in the winter when the details of the private test leaked, as part of a growing clamour for him to be called up to an England Test squad who were struggling in India.
Now, through no fault of his own, he had to confront the possibility of being labelled a “chucker” in the 2017 season. But before that, he had to amend his action, while still trying to impress on that first Lions tour.
Being omitted for the first “Test” against Sri Lanka A in Kandy was another blow – the work on his action was continuing. But he was handed his Lions debut in the second match in Dambulla and after struggling to make an impression in the first innings, perhaps two cheap wickets in the second – both stumped by Ben Foakes – represented a turning point?
He returned to Somerset, launched his 2017 campaign with selection for the MCC in the Champion County fixture against Middlesex in Abu Dhabi, and after a slow start he was soon terrorising Division One batsmen again, especially at Taunton, and now with a fast-developing sidekick in Dom Bess.
He passed 50 wickets for a second consecutive summer, had his first taste of the senior England set-up in the nets ahead of the Edgbaston Test against West Indies, and earned another Lions selection – confirmation that the slight changes to his action had not undermined his effectiveness.
But there were further challenges for Leach to confront on the Lions overseas training camp in Australia before Christmas, leading to further changes to his action.
“That was a really tough trip for me,” he reflected in Jamaica last month, after a record-breaking Lions performance in Trelawny. “But I learned a hell of a lot playing on those wickets which were totally different again.
“Watching Nathan Lyon bowl on those wickets in the Ashes, seeing how he goes about things, and trying to take things from that - I changed a few things to try and get a bit more energy on the ball. That’s gone really well.
“It’s a bit about what I’m thinking in my head, a bit about how I use my body, my front side and my delivery stride and things like that. So I’ve changed a few things, but I’m always changing a few things trying to get better and better. But I probably feel now the most on top of my game I have - it’s just about mentally trying to deliver those skills.”
He did that superbly in the West Indies, ending the first-class section of the tour with 21 wickets at an average of 20.28 – and those performances have now been rewarded with this senior England call, as a result of the unfortunate injury to Mason Crane.
Andy Flower, the Lions coach who is still in the West Indies working alongside Mark Ramprakash in the North-South Series, said: “Congratulations to Jack – everyone who has been involved with him on the Lions programme over the last two winters will be delighted for him about this selection.
“He went through a challenging period of his career last winter, so for him to go back to Somerset for the 2017 season and earn another opportunity with the Lions was an excellent reflection of his character as well as his ability.
“He found things tough again in our camp in Australia before Christmas, as he has said himself. But he really made the most of that opportunity, to work on his game and to improve his bowling in challenging conditions.
“Then when we came to the West Indies after Christmas and the conditions were much more helpful for the spinners of both sides, he exploited those conditions to earn some excellent figures, and now this opportunity in New Zealand with the senior England team.”