It had been a long time since Martin O’Neill experienced this kind of pain in an Old Firm derby. Some 21 years, in fact, since he last felt the crushing disappointment that only defeat in this fixture can deliver.After answering an SOS call not once but twice last season, O’Neill’s second coming as Celtic manager saw him go unbeaten across four derbies against Rangers.In the first grudge match of the new campaign, a Premier Sports Cup quarter-final tie, O’Neill and Celtic were given an almighty reality check. What a complete and utter shellacking this proved to be.If LASK Linz laid out the blueprint of how to beat Celtic last month when they dumped O’Neill’s side out of the Champions League, Rangers smartly followed suit.They played with an energy and an aggression that Celtic simply never matched. In doing so, Rangers delivered their best performance of the Derek McInnes era — and then some.It has been a while since Ibrox has witnessed such euphoria — and dominance — in Scottish football’s showpiece fixture. Martin O’Neill was unable to come up with an solution to stem the tide at Ibrox todayThe place was bouncing — quite literally at times — and rocking in a fashion that finally ignited McInnes’ tenure as manager.This was a statement win and a performance to go with it. Yet, in the opposing dugout, the spotlight fell on O’Neill.His team had been abject. They could not cope with the power, aggression and pace of Rangers. Once again, as was the case in Austria, Celtic’s soft underbelly had been brutally exposed.It says much about the overall standard of Scottish football at present that this is a team who went into the Champions League qualifiers as the best this country could offer.Celtic are weak; flimsy and fragile when opponents are brave and clever enough to press them high up the pitch. Plainly, they can’t cope with it.Rangers didn’t go full gung-ho with the press. But it was high enough and aggressive enough to unsettle Celtic. Especially some of their Old Firm debutants, to whom this would have come as quite a culture shock.In goal, Sam Johnstone was one of them. Preferred over Viljami Sinisalo, the experienced English keeper did not look remotely convincing in this kind of environment.Johnstone flapped at a couple of crosses and was also guilty of some slack passes which immediately invited the Rangers press and put his team under pressure.The case for dropping Sinisalo and replacing him with Johnstone looks weak. That’s not to say Sinisalo is a true top-level No 1. Rather, Celtic may have replaced a back-up goalkeeper with another back-up goalkeeper.Of the other new arrivals, Kasper Hogh offered no threat whatsoever up front. Signed for a fee of £11million, these were the games he was supposed to make the difference. Big-money signing Kasper Hogh was kept quiet during another underwhelming displayA player of proven Champions League pedigree from his time with Bodo/Glimt, Hogh is a long way from replicating that kind of form at present.Camilo Duran probably had his quietest game in a Celtic jersey so far, Sebastian Tounekti was non-existent for 45 minutes before being replaced at half-time.Mika Baur looked powderpuff in midfield and saw the game pass him by, something which was emblematic of Celtic’s performance as a whole.The really damning aspect about this result and performance from Celtic is that there had been a growing feeling that something like this was in the post.As written in these pages a week ago, their defence looks wholly unconvincing. Even in some of the recent wins over lesser opponents, Celtic have been so open and fragile.They routinely allow their opponents to have five or six really good chances in every game. They had been getting away with it, papering over some cracks.Here, against a Rangers team turbo-charged by the energy of a 50,000-strong home crowd, and as was the case against LASK in Austria, they didn’t get away with it.That is what should concern Celtic fans most of all. In their two biggest matches of the season so far, they have crumbled.They have lost both of those matches by an aggregate scoreline of 8-1. Proper teams don’t capitulate in this sort of fashion.It would be foolish to excuse this as merely a one-off or a bad day at the office. The humiliation in Austria set the tone for Celtic’s season, just as the defeat to Kairat Almaty in Kazakhstan did last term. Old Firm debutant Sam Johnstone set the tone for his Celtic side with a nervy showingOnce that kind of mood music sets in, it can become difficult to change. Until they start to show some genuine backbone, this Celtic team will be known as a team of bluffers who crumble under pressure.In these early weeks of the new season, it is Rangers who have laid down a marker. With the teams meeting once again in the league next weekend, the psychological edge is theirs.It will be difficult to replicate this sort of energy next weekend at Celtic Park when they have no away fans, but McInnes and his players at least know what the winning formula looks like.The two players who typified Rangers’ energy and industry above all others were Dan Neil and Ryan Naderi. It was Naderi who robbed Cameron Carter-Vickers of possession to spark the move which eventually saw Neil score the opening goal.There have been times in these early weeks of the new season when Neil has struggled to convince since his summer move from Sunderland. There was a belief starting to gather among some sections of the Rangers support that he might turn out to be little more than a rebranded and repackaged version of Joe Rothwell.But this was a performance which emphatically dispelled any such notions. Quite simply, Neil was the best player on the pitch — and by quite some distance.Wearing the captain’s armband in the absence of Lawrence Shankland, Neil demonstrated exactly the sort of leadership and authority that should be expected of a Rangers captain in this fixture.Over the past 10 years or so, how many Rangers midfielders can say they have dominated Callum McGregor in an Old Firm derby?They would be few and far between. But Neil glided through this match with poise and elegance, exemplified by the classy finishes he produced for both his goals.He got Rangers on the front foot and playing, turning and getting out of some tight spaces when he had to, and having a far greater influence on proceedings than Celtic skipper McGregor. Rangers captain Dan Neil was a class apart in midfield as he helped himself to two goalsThese derbies can make or break Old Firm careers. In the case of Neil, he should be the heartbeat of the Rangers midfield — and also their captain — for the foreseeable future. This proved it beyond all doubt.As for Celtic, you expect some home truths will be delivered over these next few days. They were miles off it and got exactly what they deserved.They will face Ferencvaros in Glasgow on Thursday night in the Europa League, before then renewing hostilities with Rangers once again next Sunday.O’Neill candidly admitted yesterday that this would have come as a major shock to some of Celtic’s new players. Problem is, they don’t have much time to adapt and adjust.As the old saying goes in Glasgow, you are only ever three games away from a crisis. By this time next week, it might well be a crisis.Ironically, the sort of crisis O’Neill was hired to avert last season. The problem this time around is that Celtic can’t replace Martin O’Neill with Martin O’Neill.