Sixteen years ago Martin O'Neill, a boyhood Celtic fan from Northern Ireland, left behind English football and became manager of Celtic. It was a move that ushered in a period of domestic and European success that hadn't been seen in the east end of Glasgow since the 1970s. The club haven't looked back since.

With 21 major trophies since that appointment you'd be forgiven for thinking why there's such a hullabaloo about Celtic's need for a fresh start and why they need a signal of intent at all.

The past two seasons at Celtic Park have been a curious time. Despite spirited attempts by Aberdeen to close the gap on the Bhoys, they finished 17 points and 15 points behind the eventual winners of the Scottish Premiership in each campaign.

While this dominance was more than welcomed by the Hoops faithful, the parameters of judging a Celtic manager had shifted and unrest was growing around Ronny Deila.

With lacklustre showings in Europe and faltering performances in the cups, Celtic fans had been left dreaming of more. A malaise was creeping over everything on and off the park.

The trust between the players, the coaching staff and fans had been eroded and no longer could draws or losses be tolerated. Every time points were dropped an enquiry was established, logic and circumstance be damned.

While perhaps at times there were unfair assessments of Ronny Deila, that kind of relationship couldn't go on despite delivery of another league title.

Three days ago Brendan Rodgers, a boyhood Celtic fan from Northern Ireland, left behind English football and became manager of Celtic. The feeling around the appointment of a manager has never been so gushingly positive since the days of O'Neill.

It's that refreshing unity that is so important going forward. There is no room for standing still, even at the top.

On the other side of Glasgow, Rangers have been rebuilding. Four years in the lower leagues have left the Ibrox club hungry for real success and defiant in their assertion that they are Scotland's premier football club, egged on by a resurgence of on the pitch performances under Mark Warburton.

With the appointment of Rodgers, Celtic have let it be known - come ahead. Fans needed to know that the Celtic hierarchy still have the fight left in them after a perceived downsizing of footballing affairs.

That message is apparently coming through loud and clear - there were queues out the door of the club's ticket office on Saturday after the news broke, fans eager to secure their season tickets.

It's because Rodgers offers the kind of big name status that Scottish football didn't think it could attract anymore. Prize money in the sport's biggest leagues casts a long shadow over the game in Scotland. The English Premier League's bottom club Aston Villa will earn £64m more than Celtic in prize money alone this season.

The box office feeling of this appointment is enough for some to be on board from the start. It sends out a signal not just to the fans but to the wider footballing world that Celtic mean business this summer.

The Celtic captain Scott Brown told the club's official website, "It’s definitely exciting. The players he will attract himself will be huge."

There's a truth in that. Bigger names are most certainly on the Celtic radar now, drawn by the prospect of learning under a big time manager who made a name for himself in football's highest profile league.

Celtic's recent transfer history has been spotty. For every success finding his feet in the first team there's been another unable to step up before being sent out on loan. There's never been a better time to attract the calibre of player that will make a real difference to the first XI.

Why is that? Well there are notoriously difficult Champions League qualifiers to negotiate this summer. Since the turn of century Celtic haven't gone three seasons in a row without reaching the group stages.

After missing out in the two seasons under Deila, another failure would be a significant blow to the club's ambitions. Just competing in the group stages can net Celtic another £20m-30m in extra revenue.

Nothing is guaranteed in football and battles will be just as tough on the pitch as they ever were but what this appointment offers Celtic fans is potential, a signal from the club that they still share the same ambition they do.

Every supporter is hoping that Brendan Rodgers can add an aura to Celtic Park and make it the kind of fortress, with dreams and songs to sing, that's famous across the continent once again.

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