Another Old Firm Derby. Another comfortable Celtic win.

The dominance of the Parkhead men continued in a performance that oozed class and confidence on the big stage. It was in all honesty men against boys as Celtic cantered to a 4-0 victory without breaking sweat.

As a result, it was without a doubt back to the dark days of Pedro Caixinha as Celtic strolled around Hampden Park untroubled.

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The gap that looked to have been closing under Graeme Murty after some encouraging recent performances against their bitter rivals, and a positive January transfer window looks again to be as wide as the Clyde.

To be brutally honest, the Rangers performance was an absolute embarrassment. From the first whistle to the last they just never laid a glove on Celtic and that is just not acceptable to the thousands of Rangers fans who packed into Hampden expecting at least their team to go out and get in about Celtic.

At least in the last game at Ibrox, which Celtic won 3-2, they had a go and attacked. That offered some encouragement.

In the middle of the park Scott Brown again showed why he is not only the best midfield player in Scotland, but has been the best overall player in the country this season. He controlled the whole game from deep and the sign of a good player is how much time they appear to have on the ball.

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In the frenetic heat of a Derby, Scott looked as if he had an eternity to probe and pick holes in the final third for Celtic. Greg Docherty is a very promising player who I think will go on and be a very good player for Rangers, but he will have seen the level he needs to get to for him to go and be one the best midfield players in Scotland.

Scott was immense but he wasn’t the only one in green and white hoops.

Moussa Dembele has been at best this season hot and cold. Maybe that is being a little unfair on the young Frenchman who set some really high standards, but he seems to be returning right back to his best at the business end of the season.

Having watched Dembele closely as a fellow striker since he arrived from Fulham, I have noticed that if he starts a game with some nice touches and bullies his opponent, he inevitably goes and and plays well. The first five minutes of the game yesterday his touch and hold up play was perfect.

He looked razor sharp turning both Ross McCrorie and Russell Martin inside out early doors and that set the tone for a fantastic individual performance. He eventually got McCrorie sent off and got himself a deserved goal. His attitude was absolutely exemplary.

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Contrast that to his opposite number Alfredo Morelos. Both at just 21 years old have much to learn and a huge amount of improvement in them.

What will determine how far both go in the game is for me is attitude. Dembele earlier in the season made a big mistake when he got substituted and went straight down the tunnel in the 0-0 draw against Rangers. I commented at the time it was poor and since then to be fair to him his attitude has been spot on.

He has got his head down and improved since then.

Morelos has scored a lot of goals for Rangers but could and should have at least doubled the amount. He has missed some unbelievable chances. But what has concerned me is his attitude in some of the Rangers games when he hasn’t played well or scored.

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He seems to down tools and start to constantly moan and bicker at his team-mates. His reaction to Jason Cummings when he scored a hat trick against Falkirk in the Scottish Cup was dreadful.

Strikers want to score every game. I did. But you need to play for the team. I would suggest that someone at Rangers has a word in his ear to tell him that what matters is the club winning games and trophies. Not how many goals he scores.

If it was at all doubtful that Graeme Murty would be the manager at Rangers next season, yesterday has rubber stamped he won’t be in my view. They are still so far behind Celtic that only someone with a bottomless pit of money putting serious cash in can get them close.

Celtic gambled on Brendan Rodgers and it has paid dividends. Rangers must go and do the same.