Has gap from Celtic to Rangers got bigger as Ange Postecoglou nears treble?

Five derbies, one draw, four Celtic wins, including two in cup competitions - it's no surprise Ange Postecoglou's side are on their way to a domestic treble.

The Australian is also on his way to matching the unbeaten Old Firm match runs of predecessors Brendan Rodgers and Martin O'Neill and emulating the feat of back-to-back titles set by those managers and Gordon Strachan, Neil Lennon and Ronny Deila.

So, is the gap between Celtic and rivals Rangers getting bigger?

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Bigger than what?

Last season's derbies were two wins apiece and a draw, with Celtic scoring more goals in the fixture overall. On that basis alone, yes, the gap has widened significantly. The one caveat to that is the relative closeness of the recent derbies.

After Celtic dispatched Giovanni van Bronckhorst's Rangers 4-0 in September, the first Old Firm match of Michael Beale's Rangers tenure was a 2-2 draw in December. Celtic have won the three subsequent cup and league games by a one-goal margin.

But results are all that matter and four Old Firm losses makes hard reading for Rangers supporters.

"The gap is huge at the moment," former Celtic midfielder Stiliyan Petrov told BBC Scotland. "You've seen that. In the last couple of games, probably Rangers have pushed Celtic a little bit further due to desperation. They were going to lose the league then there was the cup semi-final, a last chance for them to win something.

"But next season it starts again and what Celtic have is consistency. This is the key for Celtic. Rangers cannot have the consistency Celtic have and we've seen this for two years and it's continuing for more because if Rangers don't do anything about it that gap will just grow because of the financial side.

"[With] Champions League money, the revenue will just get bigger and bigger and Celtic will be able to run far away from Rangers in a short space of time."

'Postecoglou the difference for Celtic'

The roots of this campaign's contrasting fortunes can arguably be traced to both of the 2022 transfer windows.

Celtic, after a major rebuild in the summer of 2021, trailed defending champions Rangers by six points at the winter break stage of last season. The captures of Reo Hatate, Daizen Maeda and Matt O'Riley helped the challengers overtake Van Bronckhorst's Rangers and finish four points clear come May.

Rangers' marquee signing of the window, Aaron Ramsey, spent most of his loan spell at Ibrox injured.

The challenge for the Ibrox club in the summer of 2022 was to adapt their squad to try and compete with Celtic's, which was bolstered by established internationals Aaron Mooy and Sead Haksabanovic.

Of the seven players Rangers signed, only four have made more than 10 appearances and the other three have had various spells out injured.

Consequently, Rangers' points per game average has increased only marginally from 2.34 to 2.39. Celtic, 2.44 last season, are now averaging 2.78.

"It comes from the manager," attests Petrov, who was part of O'Neill's treble-winning and Uefa Cup final team.

"It's what the manager brings every day on the training ground, on the field, off the field. He has the same message, and that message is, 'we fight, we don't stop, we play high intensity football' and the players have inherited those good habits. Psychologically, it's a very powerful thing.

"Teams around Scotland, they fear Celtic. They've got a strong group of players who are ready to fight and follow the manager further and they're showing a great ability to fight and win matches even when they don't play well."

How far can Celtic's success go?

Celtic are odds on for the treble, which would be a fifth in six seasons. Successive trebles would therefore be the obvious next challenge for Postecoglou's side.

However, European football has been a source of frustration for the club over recent years.

Since Lennon's Celtic reached the last 16 of the Champions League in season 2012-13, teams overseen by Lennon, Deila, Rodgers and Postecoglou have only made it past the turn of the year still in Europe on five occasions and typically been knocked out by February.

"It seems like he wants to be remembered as probably the greatest and most successful manager at Celtic so what he does is continuously improve, adding, trying to get everybody challenged," Petrov said.

"'I'm here to make you better and by making you better I want to achieve, I want to win'. If he's still at the club, I believe he's going to continue doing that and that could be a big problem for Scottish football."

What do Rangers do now?

The task facing Beale now is essentially the same as the one he inherited in November. January signings Todd Cantwell and Nicolas Raskin have helped improve Rangers' results against teams other than Celtic but they are now without a win over their Glasgow rivals in a year.

Beale spoke of a significant summer rebuild on the horizon, the biggest in some time at the club. However, unlike predecessor Van Bronckhorst, the current Ibrox boss does not have a trophy and a run to a European final to buy him some time.

Rangers too will have European ambitions but the immediacy of domestic success will likely frame next season's priorities. Beale has stated a desire to get players in early and, with this season effectively over, he can get on with that planning in earnest.

"These are challenging times for Rangers," added Petrov, whose Celtic team finished second to Rangers in three of the seven years he was in Glasgow.

"They have to add, they have to improve, they have to catch Celtic. Celtic are in the driving seat. What they have to do is continue to work in the right direction, succeeding, getting to the Champions League, succeeding there and winning the league and that's what Celtic and Ange Postecoglou want to do."