Last year the 29-year-old bounced back from an ankle injury to star during the run to the Euro 2020 final, earning himself a place in the team of the tournament.
But things have gone awry since then, with a wretched season for all involved with Manchester United followed by the captain enduring a challenging start to the current campaign.
Dropped after Erik ten Hag lost his first two matches in charge, the centre-back has only made seven more club appearances - a period that also saw him laid low by injury.
Those struggles led to questions over Maguire's place in the World Cup squad and the defender admits there was a part of him, however small, that was concerned he would not make Gareth Southgate's selection.
"Obviously being picked for your country is a huge privilege," he said ahead of winning his 50th cap in Friday's World Cup group game against the United States.
"It's the pinnacle of anybody's footballing career to play at major tournaments for your country, World Cups especially. It's the biggest tournament in the world.
"Obviously you have fear of (not) being in a squad, but I had great belief over what I have done over the 49 caps I've played for England that I've earned the trust to be in the squad and be available for the team and the selection."
Maguire was thrust straight into the starting line-up for Monday's World Cup opener against Iran, whose fans had brought a few signs goading the oft-abused defender.
There can be few players that receive more relentless criticism than the world's most expensive defender, but he appears adept at brushing it aside.
Asked whether he doubts himself given the harsh background noise, Maguire said: "No, I have great belief in myself.
"I go out on the training pitch, I work as hard as possible. I give my all, I give my best and that gives you good preparation to go into a game and perform to the best level.
"I went into the Euros on the back of an eight to 10 week injury, so I wasn't too worried about the lack of game time.
"Obviously I want to be playing every week for my club. It's something that I'm going to fight to get back into the team.
"So, it's not what and where I wanted to be but of course I feel fresh.
"I've worked hard, I've worked doing extras on the training pitch to make sure I'm ready when I get the opportunity to play.
"I knew the World Cup was coming up, so I always put on the extra shifts in training, like I said, and kept myself ticking over."
Maguire is away with England at a fascinating time for United, with the Glazer family announcing on Tuesday they were willing to sell just hours after Cristiano Ronaldo's contract was mutually terminated.
The skipper says he has found it easy to focus on national team matters despite there being "a lot of talk going off around the club", and interestingly used his now former team-mate as an example for coping with flak.
"Of course as a footballer nobody likes being criticised, but I think it's part and parcel of the game," said Maguire, who feels fine after being substituted against Iran as he was feeling unwell.
"I've played with Cristiano Ronaldo for the last couple of years and he's one of the greatest players ever to kick a football and he gets criticised day in, day out.
"So, if it's going to happen to him and the position I'm in, I think it's part and parcel of the game, especially the position that I'm in playing for Manchester United and the captain of Manchester United.
"With Cristiano playing and me being around him over the last couple of years, he's the greatest player, for me, to ever kick a football and he gets criticised daily so it's going to happen to each and every one of us.
"So, it's part and parcel of the game. It's something that you've got to go into training, do your best and that's what I always tell myself. Just go in and do your best and that's only what you can do."