Rangers face Motherwell at Ibrox on Sunday afternoon.
Frank McAvennie has told Open Goal's Right In the Coupon that Rangers manager Steven Gerrard has made a mistake in dropping Nikola Katic for fellow new signing Joe Worrall.
Katic, 22, joined the Gers from Croatian side Slaven Belupo in the summer transfer window for £2million (Scottish Sun), and was instantly called upon as first choice alongside Connor Goldson at centre-back.
The Croat played every single minute of the Gers' Europa League qualifying matches, putting in some exceptional displays to qualify for the group stage. But Katic has found himself an unused substitute in eight of the last 11 games.
Instead, Gerrard has combined Nottingham Forest loanee Worrall with Goldson at centre-back, which has coincided with a dip in form. Rangers have won just three of the eight games Katic has been on the bench.
"He brought that defender in [Worrall] and it's changed a wee bit," McAvennie said. "I thought he was alright, he'd done well. You look at Rangers results, and you think he must've been doing well.
"You've got to keep our back four straightforward, not too many changes. If you can pick your back four most weeks, then that's a good team. It's about forging partnerships at the back."
Katic has plenty of competition at centre-back, with veteran defender Gareth McAuley now fit after joining the club in September as a free agent following his release from West Bromwich Albion.
The Northern Ireland international came on as a late substitute against Spartak Moscow, and he is now in contention to start against Motherwell on Sunday afternoon.
Rangers sit in third place on 21 points from 11 league games, while Celtic are in second on 25 and Hearts still remain on top with 26.