A year ago, Jack Leach was the cult hero of English cricket.

Fast forward to the present and the end of a 12-month period in which Leach has endured illness, frustration and a lack of cricket.

The left-arm spinner contracted sepsis on the tour of New Zealand at the end of 2019, then had to come home early from South Africa in January.

His time in England’s bio-secure bubble this summer was spent exclusively as a reserve, meaning his appearance for Somerset against Essex in the Bob Willis Trophy final on Wednesday will be only his third first-class match since last summer.

“It’s the ups and downs of cricket,” Leach says. “I learned when things are going well, be ready for them to not go so well. You’re never that far away from a down when you’re up. And when you’re down, you’re never that far away from being back up.”

Leach is no stranger to adversity. A sufferer of Crohn’s disease, his progress in cricket has been halted at various points by two fractured skulls, a broken thumb and questions over his action.

His illness in New Zealand, contracted following a bout of food poisoning, could have been even more serious.

“I felt like I was very, very ill at one point,” the 29-year-old explains.

“I do remember thinking to myself ‘don’t fall asleep’, because I didn’t think I’d wake up. I don’t know if that was the case, but I felt like I was fighting something pretty big.”

Leach’s next chance to play for England would have come on the tour of Sri Lanka in March had it not been cancelled because of the coronavirus pandemic.

After lockdown came the bubble and weeks of running drinks, sub fielding and net practice. From taking part in a practice match among the England players at the beginning of July, Leach did not play again until Somerset’s trip to Worcestershire on 6 September.

“If someone said you are going to do 10 weeks in the bubble as a reserve again, I would find that hard, but I’ve got so much out of it at the same time,” he says.

“There were definite times of frustration. It’s hard training as much as I have done without matches to back it up, but that is where you have to really believe in what you’re working on.

“I do feel a much better bowler now, and it’s up to me to get the opportunities to show people that I am a better bowler.”

Not only does Leach think he’s a better bowler, but also a “better person”. Rather than seeing his reserve role as a waste of time, he has worked on his game. The result is more momentum in his run-up and tweaks to get more revolutions on the spinning ball.

“It’s been a chance for me to be really honest with myself,” he says. “Sometimes, as sportsmen, we try to kid ourselves a little bit in terms of giving off confidence and pretending everything is great.

“Sometimes the best thing you can do is be honest and ask what are your insecurities when it comes to your game.”

Leach credits fast bowler Mark Wood, who also spent plenty of bubble time on the sidelines, and popular England masseur Mark Saxby for keeping him “on the straight and narrow”.

“Woody makes me laugh like no-one else and Mark Saxby is much more than the team masseur. He is such a huge part of the England culture, always there if you need a chat. More than anything else, he’s just a really good bloke. A lot of people have offloaded on him. I have a lot of respect for him.

“Chris Woakes made a great coffee, and he always had good advice. The lads played a lot of cards, which was good banter, and there was a lot of gaming.

“I wasn’t one for Call of Duty, so maybe that was when I watched something on Netflix. I watched The Office all the way through again. Ricky Gervais is always a good one when you’re struggling. I also got the odd Domino’s pizza takeaway to feel happy.”

For Leach, the Bob Willis Trophy final at Lord’s is his opportunity to demonstrate all he has worked on over the summer.

He is also prepared to spend more time locked away in a bubble if England’s proposed winter tours of Sri Lanka and India, or their home schedule of 2021, demand it.

Leach is driven by the memories of 2019, when he elevated himself to such a heroic status that one of the winners of the Guardian’s young sportswriter of the year competition wrote a story about his glasses.

“I just love the game,” he says. “I love what it’s given me. Experiencing being out there with Stokesy at Headingley – you are working for moments for like that.

“There will be ups and downs, but good has come from every down. I love the journey I’m on.”