There were a couple of moments, ahead of this Test, when you sensed the burden of carrying this England batting line-up was starting to get to Joe Root.

For one thing, he requested that the pre-match captain's press conference - which has, for many years, taken place the day before the game - be moved to two days ahead of the match to allow him time to focus before the game. And then, while talking about Ben Stokes, his voice caught for just a moment as he discussed the phone call in which his friend had told him he needed a break.

Root was, no doubt, aware of how much Stokes would be missed as a player. But the sense was much more of someone who simply felt for a colleague who was going through a tough time. You wondered whether Root might not be experiencing some of the same emotions. We really do ask quite a lot of our cricketers.

But whatever the pressure he was feeling ahead of the match, Root has shouldered his burden magnificently. Here he produced one of his finest Test centuries - there are now 21 from which to select; none of them have, to date, come in a losing cause - to keep his side in with a fighting chance in this match. Without him, England would have been blown away.

There was a period, not so long ago, when there were a few whispers about Root's batting. It wasn't that the runs had dried up exactly; it was more that the bigger scores had tended to come in relatively low intensity situations. In 2019, for example, there was a century in St Lucia, by which time the series had already been lost, and there was a double-hundred in Hamilton on a pitch so horrendously flat that only 22 wickets fell across five days.

There are no such caveats about this innings. It came against an outstanding attack, on a surface upon which other batters have struggled and when his side - still 49 behind and two wickets down when he strode out to bat - were in some trouble. Not only that, but it came at the start of a series with everything still to be defined. It was his first Test century in England since 2018 but his best at home since at least 2017 when he made 190 in the first Test of a series against South Africa.

To put his predominance in perspective, while he has made 109 and 64 in this game, the next highest score of his teammates across both innings has been Sam Curran's 32. It is, according to BBC statistician Andy Zaltzman, only the fourth time in Test history that a player has made a century and half-century in a match where nobody else in the team has made even 35. Increasingly, Root is looking a giant among them. Take him out of this side and you wonder where they would drop in the rankings. Outside the top six, you suspect.

His skills were put into greatest context during his partnership (worth 89 in 28.5 overs) with Dom Sibley. While Sibley's crease occupation was valuable, you couldn't help but admire how much easier the business of batting looked for Root. So vast is his range of stroke, so adaptable his feet and the angle of his bat, that he is rarely kept scoreless. He faced only two maidens in his entire innings - one of them during a nervous passage of play when he had 97 - and has a late cut which allows him to score from deliveries other players would look to leave well alone. Sibley made just 12 of their partnership.

But it was surely the drives, played off both front and back foot, that will linger longest in the memory. Certainly they had a packed Trent Bridge purring in delight. The on-drive that brought the century was just a little reminiscent of the shot with which Sir Geoffrey Boycott reached his 100th first-class hundred. The celebration - by Root's standards sustained and expressive - showed how important this innings was. He knew his team needed this.

More than that, though, he had made a conscious effort to try and enjoy these pressures. This is what he had dreamed of as a kid, after all. So instead of focusing on those negative thoughts - the sense that his side would collapse if he failed - instead of allowing himself to become careworn, he tried to remember he was playing the game he loves, for a team he loves and on the grandest of stages. Put simply, he tried to remember it was meant to be "fun".

"There's been a lot to handle," he admitted afterwards. "But it's important you find ways to handle that. You can let it weigh you down but you have to find solutions. It's about trying to deal with what's in front of you and not letting anything overwhelm you.

"This morning I said to myself and to the group: just remember what is fun about cricket. It might be tough sometimes, it might be hard, but it's fun. And it's really important we all embrace that. Whatever the situation, whatever the conditions and wherever you are in your own game, it's important you go out there, enjoy the moment and make the most of it.

"It felt pretty good to get a big score and get us into position to give us a chance of winning this Test."

He reckoned that batting in the ODI series against Sri Lanka had helped him regain his batting rhythm. He made 68 and 79 - both innings unbeaten - in that series and reasoned that the required tempo - positive, but without the urgency of T20 - was helpful to his game.

"I've actually felt a real benefit from playing some white-ball cricket," he said. "I know it would be nice to have some red-ball cricket coming into this game but, from my point of view, playing 50-over cricket gave me some rhythm back in my batting.

"I felt I got forward and back better. I was standing a lot taller a lot earlier, picking my bat up a lot earlier, I feel like I've got rhythm back in my hands. I find 50-over cricket can be a massive help to my red-ball game."

Maybe we shouldn't have been surprised. Root has risen in stature in recent months, producing a string of huge scores in Sri Lanka and India (228 and 186 in Galle and 218 in Chennai) that led his side to memorable victories. And while Root at times made those surfaces look pretty flat, it's worth remembering that no-one else in his side made centuries. Indeed, the next-highest score when he made that 186 was just 55.

He's already made 1,064 Test runs this year. So, with up to seven further Tests available to him this year (there are only three Ashes Tests scheduled before the end of the year this time and it's entirely possible none of them will take place), he has given himself a chance of breaking Mohammad Yousuf's record of 1,788 runs in a calendar year. More revealingly, however, the next-highest contributor for England in 2021 is Dan Lawrence with 354. In all, Root has scored 29.19 percent of England's Test runs in 2021.

Whether all this is sustainable in the long-term is debatable. At some stage, there is a danger the burden will break even Root. It is really is imperative England find a way to coax more runs out of the rest of their batting line-up. Right now, though, Root has given his side a chance to win a game they could easily have lost already without his intervention. If they pull this off, they will owe a huge amount to their captain.

George Dobell is a senior correspondent at ESPNcricinfo