KENNY MILLER believes a derby defeat would be seen as 'disastrous' on both sides of the Old Firm divide this weekend.

New Celtic manager Ange Postecoglou takes his side to Ibrox for the first time aiming to strike an early blow in the Premiership title race as they continue to recover from their defeat to Hearts.

Rangers, meanwhile, got back to winning ways in the league with victory over Ross County and have the chance to extend their unbeaten run in the famous fixture in front of a capacity home crowd.

The Old Firm are level on points in the Premiership but former Scotland star Miller knows what is at stake for both Postecoglou and Steven Gerrard come kick-off on Sunday.

Miller said: "It's a tough start to the season for both clubs because of the European games coming thick and fast, but that's the nature of the beast at this level. If you're striving for European football, you've got to get on with it.

"Neither side can afford to lose this game at Ibrox this weekend, because it'll mean they'll have lost two of their opening four fixtures this season. That's a disastrous start for either club.

"Throw in the fact that they've both been knocked out of the Champions League qualifiers already, coupled with defeat this Sunday, and you'd have to say it's a horrendous start for whichever club it happens to.

"It's early days, but this is the psychology in Glasgow. If you're Celtic or Rangers and you've lost two of your first four games, then the reality is you're going to be playing catch-up with the other side.

"It's a huge, huge game, not least because the team that wins the league this year gets an automatic Champions League spot, so this really is massive.

"The financial gain that comes with that in Scotland is huge. What an incentive to win the title; you can swap all of this qualification process for an automatic group spot."

Rangers will head into the Old Firm cauldron with plenty of experience on their side and the form book in their favour after avoiding defeat to Celtic throughout their 55 winning campaign.

Postecoglou's side, however, will have several derby debutants at Ibrox as Celtic attempt to pile the pressure on the champions and lay down a marker of their Premiership intentions.

The stage is set for a Old Firm hero to emerge and Miller is well aware of the pressure that both sets of players will be under having crossed the Glasgow divide during his illustrious career.

"I was fortunate enough to get a decent goal return in the Old Firm, because it can make or break a player," Miller, speaking exclusively to Ladbrokes, said. "That fixture brought the best out of me.

"I loved the occasion, I relished the challenge. You need to love that fixture; it has to be the first fixture you look for when they get released at the start of the season.

"You need to thrive on it, because there's so much pressure going into it. There's an incredible amount of fan expectation.

"If you go under when things are going against your team in that fixture, fans will turn against you, make no mistake about it., And they're a tough crowd to win over.

"If I'd never have scored the goals I did in the Old Firm, and I'd have missed chance after chance, I'd never be forgiven. I could score goals in every other game in the season and fans would say 'yeah but you missed a sitter against Celtic which cost us the league'.

"These games can have a big, big say on which way the title goes. There aren't many seasons where the league is a landslide, so the games always have extra meaning."