Between 2020 and the end of last season, Butland endured arguably the most frustrating period of his career, making just 17 appearances in all competitions.
Each of those outings came in the colours of Crystal Palace, only when first-choice Vicente Guaita was unavailable for selection.
A loan spell at Manchester United also proved unproductive with Butland not making a single senior outing, but it did not stop Rangers from pushing to secure his signature in the summer.
Since then, the 30-year-old has made huge strides in reviving his career, featuring between the sticks on 17 occasions North of the border.
Eight clean sheets have been recorded by the former England international, Rangers seemingly having secured a suitable long-term alternative to Allan McGregor.
However, reports have recently suggested that Birmingham City - now managed by Wayne Rooney - are interested in signing Butland, despite his short stay at Ibrox.
The ambitious Blues hierarchy are allegedly open to securing a deal for the club's former player during the January transfer window.
According to Football Insider, Rangers are hoping to fend off any admirers by setting Butland's asking price at £5m.
That is despite Rangers only signing Butland on a free transfer as recently as the start of July, but such a stance highlights the impact that he has made in Scotland.
The report claims that the Rangers board are confident that Birmingham or any other suitors will now shy away from one of their key men.
Butland holds a four-year contract and there is no indication that he would want to return to English football given his recent progress with regards to game time.
Birmingham would also need to get current deputy Neil Etheridge off the wage bill before they could contemplate an ambitious bid for a player who came through their youth academy before making 46 senior appearances.