Hogh’s barren run continued against Besiktas as he failed to score for the 15th successive match, despite Martin O’Neill praising other aspects of the Dane’s performance.

The Celtic boss highlighted Hogh’s strength and hold-up play following the Europa League victory, but Boyd is far less convinced. Writing in his Scottish Sun column, Boyd said: “Martin is clearly trying anything to boost Hogh’s confidence after a 15-game drought.

“But let’s be honest, Celtic’s record transfer deal is fast turning into a catastrophe.”

Boyd pointed to the reaction inside Parkhead when Hogh found the net after an offside flag had already been raised. “There were ironic cheers from Parkhead fans when the No 9 rolled the ball into the Besiktas net after an offside flag went up,” he added.

“When your own support is mocking you, it’s clear that all is not well.”

Boyd also dismissed the suggestion that Hogh should currently feature in O’Neill’s strongest starting XI. “If the Celtic manager is naming his strongest team right now, Hogh is NOT in it,” he said.

“Celtic are a far better team with the Colombian playing as a No 9. That’s not even up for debate.

"There’s more speed and threat to their play with Duran up front.”

And Boyd’s assessment became even more damning as he considered Hogh’s prospects of retaining his place against Kilmarnock. “Martin will be wondering what he can do with the out-of-sorts Dane, but right now, he doesn’t deserve a place in the team.”