One year ago, Brendan Rodgers resigned as Celtic manager, with Martin O'Neill immediately taking the reigns in what the Scottish champions thought would be an interim period in charge.

Twelve months on, O'Neill is still there, albeit over two spells with 33 dismal days under Wilfried Nancy squeezed in between.

So where are Celtic at in terms of "moving forward", that cliched business term that has seeped into football parlance?

Shortly before his exit, Rodgers described the Celtic squad as "a Honda Civic rather than a Ferrari" as he bemoaned transfer spending, but how much longer will it be steered by his 74-year-old successor?

'Long year' has 'rejuvenated' O'Neill

O'Neill had admitted he considered his position during the last international break, but he showed no signs of being ready to walk away when addressing the media before Wednesday's meeting with Dundee United.

Asked how he looked back on his latest year in charge, he replied: "Obviously with a lot of satisfaction and secretly probably delighted to get the call and happy with the results since. So it feels like a long year. Very long.

"The club has done more for me than I've done for the club in that sense. Seriously, it's rejuvenated me in many aspects."

Previous to his return, O'Neill had been "semi-enjoying my life watching the game from afar" and "talking nonsense most of the time" as a football pundit.

However, he was delighted with the opportunity to return to "a game that I absolutely love, will love forever".

Six out of 10 domestically?

Rodgers' second two-year spell as Celtic manager came to an end after a 3-1 defeat at Hearts that left his side eight points behind the Edinburgh side after nine games.

They had lost two of those nine, scoring 12 goals for the loss of eight.

Despite Hearts retaining their lead until the final day of the season, Rodgers' fellow Northern Irishman would turn it round in the end with a dramatic victory over their title rivals at Celtic Park to secure their 56th league title and fifth in a row.

This season, O'Neill's side have lost only one of their 10 league games, scoring 25 times for the concession of six, to lead Rangers in the title race.

On the surface, 16 wins in 17 league games since the closing stages of last season looks like progress.

As Celtic podcaster Tino Callaghan told the BBC's Scottish Football Podcast: "On the last day of the season - 16 May - everything did turn out fine and dandy.

"Currently, things are six out of 10 at Celtic. We're four points clear at the top of the league this week's midweek card can see us extend that lead, but things are far from correct in terms of the evolution of the club and the progress of the club."

Squad 'woefully inept' in Europe?

O'Neill's win percentage of nearly 75% in his latest spell is similar to his club record level during his trophy-laden five years in charge to 2005.

However, the recent 7-1 thrashing of Hearts apart, performances this season have largely left the Celtic support underwhelmed, while it is results in Europe - and two defeats in a week by city rivals Rangers - that have caused most alarm.

When Rodgers left, Celtic had won eight games, drawn four and lost four overall at the start of last season.

This season, they have won 11 and lost six, but on their way to a Champions League exit and to the foot of the Europa League after three games, they have suffered heavy defeats against LASK, Ferencvaros and Benfica.

"O'Neill domestically is more than capable," Callaghan said. "But the Celtic squad is woefully inept when it comes to European football and you just need to have a glance at that for evidence when you look at the bench on those European nights."

That led former Celtic striker Chris Sutton to describe the side currently under his former manager as flat-track bullies only able to dominate in Scottish football.

"We're just falling way, way behind," Callaghan agreed. "But it wasn't that long ago where we were competing with Bayern Munich and beating Leipzig and pulling off some really decent results."

Board using O'Neill as 'human shield'?

Last season was also marked by a damaging split between the board and sections of the support unhappy at the level of investment in the squad and the general running of the club.

The two sides united for last season's victorious climax to the season, but the splits have re-emerged.

"Ultimately it always comes down to recruitment, doesn't it?" Callaghan said. "I hear folks talking about entitled Celtic fans, but millions of pounds in the bank is no use unless you're spending it.

"It's about spending more effectively and it's spending certainly more efficiently and sooner within the window.

"The start of the window was exciting. Camilo Duran is a brilliant player. As good a signing as we've made in some time, Mika Baur the same.

"But the defensive midfield has been a serious issue. We haven't signed anyone there and you're now starting to feel sorry for Callum McGregor - he's been hung out to dry."

Daily Record football writer Michael Gannon agreed that O'Neill had been used as a human shield by the board.

"I feel for him a little bit because he's the only person at Celtic who fronts up and faces questions on a regular basis," he said.

"A lot of the questions, like where is the full-time chairman, where's the head of recruitment, where's the director of football, what's happened with the Green Brigade bans and fan problems, are not really for him to answer."

O'Neill 'conscious of his legacy'?

Callaghan appears to speak for many fans for whom O'Neill still feels like a stop-gap "holding position for all concerned".

"But, within that year, he's won a league and he's won a Scottish Cup as well, so not too bad," he said.

"I don't see him staying beyond this year. I think from his point of view, European football at Celtic became a thing again under O'Neill and I do think part of his decision-making in the summer to return will have been the prospect of a final chance at the Champions League, final crack at the big time.

"And he'll have been as devastated as anyone that we fell short against LASK. And I do think there's still a bit of a hangover amongst the players from that one."

After a poor start to the Europa League, will O'Neill now make finishing on a high domestically his priority?

"He will be conscious of his legacy whether he says so or otherwise and I think, whatever happens, he'll want to certainly move on this summer, if that is the case, with another league title under his belt," Gallacher added.