BRENDAN Rodgers’ motivation for these games is his fear of losing to Rangers. Goodness knows why.

Why would he lose sleep over such a spineless opposition, one so lacking in flair, organisation and even an ability to complete the absolute basics which a kids’ team would be able to carry off?

Make no mistake, Celtic didn’t just win 4-0 yesterday, they made fun of their old friends on and off the park. What was it Scott Brown said? “They can cheer if they like, but not tonight.”

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Moussa Dembele did a Panenka for his penalty, Celtic’s third, Olivier Ntcham was allowed to make it 4-0 from the spot almost as if he was given a go for a bit of a laugh. Leigh Griffiths balanced the ball on his head when he went to take a corner in the closing minutes.

Rangers players’ names were loudly chanted. By the Celtic fans.

This is the end of Graeme Murty’s chances, albeit they were slim before this semi-final, of landing the job of Rangers manager beyond this season. There is even a case which could be made for taking him out of the firing line today for his own sanity.

There is a visit to Celtic Park coming up and there is no guarantee that they will finish second or third in the league. He does not deserve to go through this.

Celtic were good yesterday and enjoyed great moments. They have some terrific players who turned up; nobody better than Brown who could have made time for a cup of tea so easy did he find his job of running the game.

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But none of this is a mystery. Rodgers always plays 4-2-3-1. Brown is the one who sits deep and must be stopped by whatever means. Kieran Tierney has licence to bomb down the left. Tom Rogic operated in the same area of the pitch he always does. Oh, and the weak link is at the back where, if closed down, the central defenders are prone to making mistakes.

And, yet, all of this seemed to come as a complete mystery to Murty and his players. It was as if they hadn’t gone nine games without beating Celtic. Rangers, quite bizarrely, only started playing when they went a man down and, even then, Craig Gordon brought off three incredible saves, one from Alfredo Morelos when lying on the ground.

This was a trouncing, a humiliation. I have been watching and covering these matches for, it seems, a thousand years, and I’ve seen some great, good, unpredictable, and downright awful Celtic and Rangers teams.

There were times in the 1990s when Rangers were on another planet but Celtic were still, on occasion, able to win this fixture. I cannot remember a worse performance from Rangers in an Old Firm game.

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Murty is a decent man but is making mistakes like a rookie manager, which is of course exactly what he is.

There was a moment in the second half, and the game was gone by that stage, when Rodgers told his midfielders they needed to spread out more. A few yards down the touchline, Murty clapped his hands.

Why not put Jason Cummings on at 3-0? Really, what did he have to lose? Instead, Jason Holt was the third substitute. What in all honesty was he going to bring to the party? In fact, he got the wrong side of Patrick Roberts and brought down the winger for the second penalty.

There were no leaders in blue. Nobody went looking for the ball. And when in possession, which was infrequent, their passing was atrocious. Morelos had lost it by the end, his new bad miss haunting him, and there were a few words said between team-mates.

Olivier Ntcham was magnificent. It’s going to be exciting seeing him develop. Mind you, it must be easier for a midfielder when the opposition don’t have a midfield. Moussa Dembele was superb in the first half. Callum McGregor had perhaps his best game in a Celtic jersey. Tierney owned the left wing.

Read more: Matthew Lindsay: Hampden humiliation was inexcusable - it's hard to see how Rangers manager Graeme Murty can survive

It didn’t take long for it to become apparent this was going to be a long day for those wearing blue. Well, apart from Andy Halliday who was substituted before half-time, perhaps for his own sake, but then appeared to get into a shouting match with a fan.

That summed up their day. Nothing went right. Dembele hit a post after five minutes and as the crosses came and shots reigned in on Wes Foderingham’s goal, it was a question of when Celtic would score. When McGregor doubled the lead, Tom Rogic’s opener was wonderful, the question then changed to how many they would win by.

After the second goal, Brown raised his arm in triumph towards the Rangers support in the main stand. It was him saying that he was better, his team were better, and they were going to win again. Deep down, those shouting insults back at him knew he was right.

Things have to change at Ibrox. Again. Thousands streamed out of the Rangers end before Ntcham even put the ball on the spot for the second penalty. Rangers, at this moment in time, have lost the supporters.