Will Jacks was supposed to be going to Edinburgh last month to celebrate his mum’s 60th birthday.

Instead, what the England all-rounder thought was a “tummy bug” turned out to be appendicitis.

From there, a rushed visit to the Royal Infirmary of Edinburgh and emergency surgery followed.

“It was just really bad really quickly so we had to go,” Jacks, 27, said.

“It was, obviously, completely random and quite scary. I was lucky to be looked after really well by the NHS.”

Jacks was given an initial four-week recovery period but ended up returning a few days early to captain the Lions in a warm-up against Sri Lanka on 11 September.

Afterwards he played in all three T20s in England’s series sweep against the same opponents, and on Tuesday took career-best 50-over figures of 5-22 in the first one-day international in Chester-le-Street.

“Luckily they were able to do a slight incision and not have to rip me open completely,” he said.

Appendix operations are not rare but they do not fit naturally with the twisting and turning of a spin bowler’s action, meaning Jacks has been doing extra work behind the scenes to rebuild his core strength.

It makes the 4.3 degrees of turn Jacks found at Chester-le-Street – the most he has produced at home in his ODI career – even more impressive, albeit helped by a slow pitch.

His figures were also the second best by an England spinner in one-day internationals.

“It was more of a confidence thing,” he said.

“It helped that we were playing the T20s first and I was bowling a maximum of four overs.

“If I am honest, I only bowled five days before the first game because I was building up my strength and trying to get some fitness back.

“I didn’t bowl too much in the T20 series, which probably benefited me. It has been OK.”

Jacks’ match in the north east also included an important 46 not out with the bat.

Though he was eventually left stranded, he batted responsibly, hitting only one four in his first 43 deliveries, to make sure England’s innings was extended from 211-7 in the 39th over to 265 in the penultimate.

“I came in and found it really difficult to start off,” he said.

“I just re-evaluated what I thought was a good score and obviously what then happened with wickets falling around me a change of the role, just try and bat out the overs.”

For so long “batting out the overs” has not been the England way, but Jacks is a player growing in maturity.

He is also vice-captain to Harry Brook for these Sri Lanka series in the absence of Jacob Bethell and has become an increasingly vocal member of the group.

It was telling that when England’s T20 World Cup campaign began earlier this year amid the cloud of Brook’s Wellington episode, Jacks was first put up to speak to the media.

“He’s just a good leader,” Brook said, plainly.

Reliable off the field, Jacks is becoming increasingly so on it.

It is 18 months since he moved from the top of the order to the middle as England’s finisher in T20 and 50-over cricket.

After obvious success as England’s player of the tournament at the T20 World Cup in India and Sri Lanka, this was another sign of his growing confidence and ability to do what is needed. Finishers rarely arrive in ideal situations, but their impact can often be match-defining.

“I feel very comfortable going out there on the day and any situation can arise which I really enjoy,” Jacks said.

“It is not the same every day which you get opening so it keeps that fresh element to the game.

“At the beginning of my career it felt like you are just fighting to play in the next game, which is not the best place to be.

“It is a luxury to know, say when we go to Headingley [for the second ODI], that I will be in the team. You can’t take that for granted and appreciate the hard work you have done to get there.”

It is also easy to forget Jacks began the year in England’s Test side, as their spinning all-rounder during the Ashes – a role now filled by Dan Lawrence.

Jacks, who met new Test coach Stephen Fleming when the New Zealander joined the white-ball squad at Old Trafford last weekend, has is signed up for a stint with MI Cape Town in the SA20 this winter.

There would no clash there with Fleming’s first tour in charge in South Africa over Christmas, but the later part of the T20 competition overlaps with England’s two Tests in Bangladesh, where English spinners will be needed.

“I don’t know about what would happen or even if they would want me,” he said.

“We will finish the summer before getting into the winter.”

For now, Jacks will focus on white-ball trips to Pakistan, Australia and South Africa as England build towards the 50-over World Cup next autumn.

One downside of a Test recall would be losing more time to rearrange that Edinburgh trip.

“It didn’t go how we planned but we will have to find time to redo it,” Jacks smiled.