AS nightmare debuts in the Glasgow derby match go it was about as bad as they get.

Up there with those endured by Ian Andrews, Scott Marshall or even Joey Barton over the years. Letting in five goals on his first appearance in the world-famous fixture is a harrowing experience it will take Jak Alnwick some time to recover from.

But where would Rangers have been yesterday without their replacement goalkeeper? He denied Olivier Ntcham twice early on, tipped a volley from the same player wide in the second-half and then produced two instinctive saves from James Forrest in the closing stages.

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Without him, the visitors could have suffered the ignominy of losing by a record scoreline. Their hosts could easily have reached double figures had he not pulled off so many fine blocks.

When Callum McGregor prodded an Odsonne Edouard cut back beyond Alnwick to put Celtic five in front early in the second-half there was well over half an hour of regulation time left to play.

The only negative for the winners was they failed to build on their tally after that and make history by racking up their greatest victory over their city rivals. The one positive for their opponents, meanwhile, was they avoided that fate.

None of Graeme Murty’s men received pass marks on what was another painful afternoon for their supporters. Some were so poor once again they may very well be moved on in the summer.

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Few of their fans will mourn the departure of Daniel Candeias, Jason Cummings, Graham Dorrans, Andy Halliday, Jason Holt, Russell Martin or Josh Windass after this gutless display. But Alnwick, standing in for the injured Wes Foderingham, deserves great credit for keeping the margin of defeat down.

The 5-0 reverse was their heaviest ever in a league game. They have been playing the team from the East End of Glasgow in that competition for 127 years, since 1891, and have not been defeated by so many goals. But it was not as humiliating a loss as the 7-1 annihilation they suf1fered in the League Cup final in 1957. It could, however, very easily have been.

Celtic certainly clinched their seventh consecutive Scottish title in fine style. It is the first time in 39 years, since that famous decider back in 1979, they had won that tournament with a win against Rangers. Over 50,000 of their fans savoured the occasion and then some.

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Still, there was a definite feeling of what might have been at the end of the 90 minutes. “We should have had seven,” said their manager Brendan Rodgers after extending his unbeaten run in the derby to 11 games. “But we’ll take five.”

His opposite number Murty declined to carry out his media duties. He had been looking for his men to bounce back from the 4-0 loss they suffered in the William Hill Scottish Cup semi-final at Hampden a fortnight earlier and revive his slender chances of being retained as manager. But there is no possibility of that happening now.

Celtic dominated from kick-off to the final whistle. Odsonne Edouard opened the scoring in the 14th minute after some excellent work by Kieran Tierney down the left flank and netted an impressive solo effort four minutes before half-time. James Forrest slotted home the third, his first in the fixture, with an individual goal that was every bit as good shortly after. He beat three men before drilling the ball into the bottom left corner.

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Tom Rogic built on his side’s t just two minutes into the second-half. Then the excellent McGregor got in on the act with what was the tenth goal that Celtic have scored against Rangers without reply.

Alastair Johnston, the former chairman and current director, had inadvisedly claimed that Rangers were “ahead of the curve” in their recovery from years of corporate vandalism after the semi-final. But this showed they are well and truly behind the eight ball if not right back to square one.

Steven Gerrard in his prime would struggle to make a difference as a player so it is very difficult to see what such an inexperienced coach will do if, as has been widely mooted, he agrees to taking over as manager.

Scott Brown and his team mates now have the chance to become the first Scottish team to win back-to-back domestic trebles if they can overcome Motherwell in the Scottish Cup final next month. It is hard to envisage them losing that outing or their domestic dominance being challenge any time soon after this rout.