Keaton Jennings dug deep to deliver a career-reviving century for England, then laid bare the scale of the anxieties and self-doubt he has experienced trying to prove himself over the past 18 months.

Jennings batted with dogged determination for more than six hours in Galle, finishing 146 not out, having painstakingly manoeuvred his team into a winning position over Sri Lanka on day three of the first Test.

It was a match, and a tour, many felt the Lancashire opener should not even be part of after a dreadful summer in which he averaged just 19.2 in 10 innings and looked bereft of confidence.

Having earned a reprieve from the selectors, he has paid them back in spades, grinding a weary Sri Lankan attack into submission through sheer force of will. Most of his six batting partners were more fluent, all of their stays more fleeting.

By the time he was done, England had declared on 322 for six and the hosts were facing up to a world-record chase of 462 on a wearing pitch.

Since scoring a hundred on debut against India in 2016, Jennings has been on a roller coaster — losing form dramatically, axed soon after and then having his technique picked apart ruthlessly on his unsuccessful return this year.

“The relief is something I can’t really explain. It’s just really pleasing and it’s a big ‘thank you’ to the people who have stuck with me over the last 18 months,” he said.

“You have to look at your immediate circle who are there when you need that hug, that shoulder to cry on. My mum and dad have been really good. My uncle too. It’s been really tough, but I sit here really proud.

“They have backed me through some tough times, waking in the night panicking and stressing and going through some tough times.

“When you’re waking up at 6.30 in the morning and reading about your technical deficiencies, it’s not human to say it wouldn’t affect you.”

It is unusual, and unusually refreshing, to hear an elite athlete opening up in such a way. Jennings has always been assiduously polite, even when under severe scrutiny, and there was no chance of him using his platform to settle scores with his critics.

Instead he simply revealed how deeply their words had hit him and how he went about bouncing back.

He added: “You feel the pinch from the media point of view. You read things and that doubt gets created, the pressure gets created to the point where I suppose you wake up and doubt what coffee you’re having in the morning … something as simple as that.

“So you try to ask yourself: ‘Where is this pressure coming from?’ It is just from a lack of runs. The key was having a happy environment away from cricket.

“Cricket is a job — what is it, 8am-7pm? — go home and enjoy a beer, enjoy a rum and coke, enjoy time with your niece and nephew. Be with your family. Actually have a life outside of cricket. I think at times, this year and last year, it’s kept me sane.”

All he needs to cap a memorable week by the Indian Ocean is for England’s bowlers to take 10 wickets over two days and prevent the hosts racking up a historic fourth-innings chase.

“Any time you put in a performance that enables your side to get into a match-winning position is really awesome and, hopefully, we can go on and win this Test,” he said.