Alex McLeish has warned Rangers striking duo Danilo and Cyriel Dessers they must step up to the challenge at Ibrox.
The former manager reckons there is more to come from the forward pair and urged them to "bare their teeth" after being left disappointed with their output against Celtic.
Speaking to the Scottish Sun, McLeish said: “We’ve still to see these new guys bare their teeth.
The Celtic game was disappointing as they had a couple of rookies in defence, and the Rangers centre-forwards never laid a glove on them.
“I don’t mean that in a bad way, but they should have been running them ragged.
“Fair play to the two young defenders, they came out of it with flying colours. But from Rangers’ point of view the forwards didn’t turn up."
For McLeish, there is no better example for the new Rangers strikers than Ally McCoist and Mark Hateley. He reckons Danilo and Dessers must follow that lead to establish themselves and become future club legends.
Cyriel Dessers was ruled to have fouled Gustaf Lagerbielke against Celtic leading to Kemar Roofe's strike being ruled out after a VAR check in a hotly-contested decision.
However, McLeish has urged the forward to be even more physical going forward - even if he must be mindful of VAR in the modern game.
He added: “I know Danilo suffered a bad injury at the weekend, so it looks like he’ll miss Thursday.
“If Dessers comes back in, should he show more physicality? Too right.
“We know the rules are different now, players don’t get away with the niggly things of years ago because the camera picks everything up.
“But you’ve still got to be robust and impose yourself on your opponent, especially centre- forwards against defenders.
“Imagine what Ally McCoist and Mark Hateley did in the past.
“The Rangers boys must establish themselves to that kind of level. That’s the task ahead for them.
“They have to assert themselves to become future Rangers legends. That has to start right now.
“With the likes of Dessers, he has to bare his teeth."