That it was to Leicester City was probably the hardest thing for Celtic fans to stomach.

‘You traded immortality for mediocrity’ was the banner that appeared in the away end at Tynecastle, days after the idolised Celtic manager’s sudden return to the Premier League. Mediocrity may have been a tad harsh given the Foxes had become Premier League champions just a few seasons earlier, but the perception was Rodgers had walked away from a historic third consecutive treble at Celtic to compete in the mid-to-lower reaches of England’s top-flight. He did not see it that way.

Leicester do not have anything like the global fanbase of Celtic, but modern football’s food chain cares little for such details. Supporters chanted weekly about Rodgers marching to 10 in a row, but beneath the adulation there was always the gnawing suspicion that his ultimate ambition was to return to the Premier League. The problem with getting there was always going to be doing so in a way that did not burn bridges at Parkhead.

Rodgers’ reputation in England had taken a hit by the way his Liverpool tenure ended. Looking back, it was all rather unfair on a man who so nearly ended a decades-long wait for a title with a hugely unfancied squad. They were never able to kick on from there, and Rodgers was sacked in October 2015.

A highly ambitious coach, it will have always been on his mind to claw his way back to that level, but jumping from Celtic to one of the Premier League’s traditional seemed a remote prospect, especially considering his European record in Glasgow was indifferent.

But Leicester was not simply intended as a stepping stone. Rodgers was impressed by their ambition, immediately setting aims to bring European football and a trophy to the King Power Stadium. Celtic fans took considerable joy in watching their former manager lose his first match to Watford via a 92nd minute Andre Gray winner. It was, however, not a sign of things to come.

Unless you leave with a club with an indisputable legacy, there’s a tendency for managers to be remembered for how things ended over what had come before. There is no denying Rodgers quickly set Leicester on an upward trajectory.

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By December 2019, the club had offered him a new deal after seven straight Premier League wins elevated his side to second. It was not only a reward for his work, but an insurance policy against already-appearing links to other clubs, namely Arsenal.

There was to be no unexpected exits, though, as Rodgers came within a whisker of Champions League qualification. Leicester were sitting fourth after 36 matches but lost their final two games to Tottenham and Manchester United, part of a wider run of just two victories in nine.

It somehow made the Europa League feel like a consolation prize, but the improvement in a team previously languishing in no man’s land was stark. Belgian midfielder Youri Tielemans was a revelation and the evergreen Jamie Vardy scored 23 goals.

The following season, Rodgers delivered on his second aim as Leicester won the FA Cup for the first time in their history. It was the crowning achievement on top of another impressive Premier League campaign, albeit once again tinged with a sense of what might have been.

Once more in position for Champions League qualification, Leicester again lost their final two matches and dropped into the Europa League. They had spent 36 games inside the top four and it was no exaggeration to suggest they were on course to consistently challenge in the Premier League’s upper echelons.

But it has been demonstrated over and over that breaking into the elite and staying there are two completely different things. The summer after their FA Cup win and Champions League near-miss was as important as there had ever been; the chance to really press on and back a manager who had made them a credible force.

Rodgers had made good on the two objectives mentioned in his very first press conference and was determined that the club did not bounce off a glass ceiling, but smash through it. It was the perfect time to do so with Arsenal and Tottenham falling away, Liverpool regressing from the prior year’s title win, and Manchester United not entirely convincing despite finishing second.

The summer that followed, however, now looks like the beginning of the end for Rodgers’ ambitions. Leicester signed Patson Daka, Boubakary Soumare Jannik Vestergaard and Ryan Bertrand, as well as securing a loan deal for Ademola Lookman late in the window.

The arrivals were not particularly successful. It was hardly stellar backing given what Rodgers had achieved to that point, but there was suggestion that he was not entirely blameless. Vestergaard, Lookman and Bertrand were perceived to ‘Rodgers signings’, whereas Daka was identified by the club’s recruitment team.

Bertrand was sidelined from Boxing Day 2021 with a long-term knee injury but even then only managed four appearances beforehand. Leicester have tried to move Vestergaard on, unsuccessfully, during the past two windows. Lookman joined Atalanta on a permanent contract after his loan ended.

Leicester finished eighth that season. In a cruel irony, it was the strong late season form that had deserted them the previous two years that dragged the team up from 14th across the final weeks. But the reality was the Foxes had not kicked on from a position of strength and promise.

When they were knocked out of the FA Cup as holders by Championship side Nottingham Forest, Rodgers unleashed on his players. He branded them ‘embarrassing’ and ‘lacking hunger’ in a startling post-match interview in which he also stated: ‘That’s why a lot of these players are not top players.’

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Ever ambitious, Rodgers expected a high personnel turnover that summer. He was left disappointed when it did not materialise. By the time the transfer window closed, he freely admitted the squad had not been furnished with necessary additions.

Leicester did not sign anyone until August 12 – backup goalkeeper Alex Smithies who has yet to make any appearances, an especially puzzling development considering long-time number one Kasper Schmeichel had been sold to Nice.

Wesley Fofana also departed for Chelsea on August 31 to be replaced by Wout Faes the following day, Leicester’s only meaningful transfer of the entire window. There were now growing similarities with the recruitment frustrations which festered in the latter months of Rodgers’ first stint at Celtic, when it’s believed he felt the club were unwilling to push the boat out on signings, the case in point being losing John McGinn to Aston Villa. Rodgers was also interested in Timothy Castagne, who he later brought to England.

Leicester started the season in disastrous fashion, and it was widely expected Rodgers, already under some pressure, would be sacked after his side failed to win any of their first seven league matches.

Having previously spoken of Europe and silverware, he had pivoted to survival mode as early as September 3, speaking of a need to simply reach the 40-point mark so often regarded as needed to guarantee safety. There was a feeling he had lost some enthusiasm for the job, and that his press conferences began to feature regular questions about whether he was happy at the club was especially telling.

A modest revival of four wins from five dragged the club away from danger, but form nosedived once more after the 2022 World Cup and Rodgers eventually departed on April 4 this year. It was a hugely disappointing conclusion to a managerial tenure which had delivered plenty and promised even more.

In the end, it appeared to boil down to Rodgers not getting the players he wanted, albeit his failure to properly address defensive frailties was not entirely down to insufficient recruitment. Such issues around signings will not have been lost on Celtic as they sought to tempt him back to Glasgow, and all the indications are his return has been facilitated by the club getting on-board with his plan to establish the Premiership champions as European contenders. That will certainly not be a cheap endeavour.

His grand plans for Leicester may not have been made reality by his bosses, but it would be extremely harsh to regard his reign as not having been largely successful. Whether it be at the King Power or Celtic Park, Rodgers has aimed consistently high with his ambitions.

If Celtic can match them, who knows where he may take them this time…