Rangers v Celtic: Halting unbeaten run not enough to paper cracks, says James McFadden

Regardless of what happens at Ibrox on Sunday, the end of an era is being heralded on the other side of Glasgow.

Celtic's dominance looked untouchable a couple of seasons ago. Even last year with Rangers getting stronger, the bid for 10 in a row looked strong.

But the Parkhead club has gone from dreams of a perfect 10 to trying to be the team to stop their Old Firm rivals finishing their title-winning campaign unbeaten. I'm not sure even halting that record can be seen as a positive now.

They've fallen way short. They've not won a trophy for this campaign, albeit last year's Scottish Cup was won - only just - on penalties against Hearts in December.

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There are wholesale changes needed at Celtic, and it's getting to the stage where they just need to get a manager in to take them forward. It looks and feels like it's the end for this current Celtic group.

You don't know who the manager is going to be next season for a start, or what style they'll play.

Celtic fans will be looking for clarity on what's next. There's been chat of Eddie Howe, with the hope that a man with Premier League experience can have an impact like Brendan Rodgers did.

It's easy to look at the job he did, but Brendan didn't arrive at Celtic Park in the same circumstances. They weren't rebuilding, they were winning.

Someone should be in by now. Celtic need to find someone who already has a plan. They can't get to the summer and have a panic on.

Rangers will strengthen in the summer, and if their rivals are to look upon this season as a blip they need a manager who will work on recruitment as soon as possible.

'Unfair to attribute downfall on Brown'

Celtic also won't have the same leader in the dressing room to help steer whoever comes in.

Scott Brown's time at the club is in its final stages now. A lot of people have said Scott's not been at his best this season, but that's unfair.

The danger is people saying 'Scott Brown's done, legs are gone, time to move on'. Some of Celtic's better performances have come with him in the team.

He's maybe not running around like he did four or five years ago, but when he sat as the anchor in midfield, he ran the show for me. At the base of the diamond or the central one of the three, he still had a huge part to play.

Scott will be a big loss. The foreign players talk about about how welcome he made them feel and showed them what it meant to play for Celtic, and managers praise him for his loyalty. Now someone else has to step up to say 'We won't have this again'.

To say the slump is partly because of him is wrong - across the board, no one's been near the level of consistency required. Celic haven't mounted a title defence to get anywhere near being close to Rangers.

It's not been good enough as a whole. In Europe they've been really poor, too.

Sunday's game may be seen as a big but Celtic had a chance in the Scottish Cup last month to put in a big performance. I know people say they created chances and should have done better, but ultimately they lost.

For Celtic, it's just get to the end of the season and get a manager in as soon as possible, and build for next season quickly. Because it has been a disaster this year.

James McFadden was talking to BBC Scotland's Scott Mullen