Barry Ferguson says Rangers need a dominant midfielder before the transfer window closes.
Derek McInnes has already brought in Cammy Devlin, Vanja Dragojevic, and Dan Neil this summer.
But Ferguson believes another addition is required.
He said (RecordSport): "As a former midfielder, I can't help looking at another area of this Rangers team – the engine room.
"And for me, they still need a dominant force in the middle of the park.
"When things are tense and edgy out there – like it was at times the other night – they could do with someone who gets them together and says: 'Calm down'.
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"Rangers need an orchestrator. That's the best way I can describe it.
"All of my pals are crying out for someone up front or wide players. I get that.
"When I look at the midfield, I see a lot of good players in there who will get better.
The transfer window in Scotland closes on Thursday, September 3 at 5pm.