The 25-year-old has been a key man for the Millers over recent seasons, winning the Player of the Season award for the 2022-23 term as the Yorkshire club avoided the drop in the Championship.
This season looks set to end in different circumstances, though, with Leam Richardson's men failing to put up a real fight for survival this time around.
Despite four clean sheets and a glut of top-class saves from goalkeeper, the Millers are rooted firmly to the bottom of the Championship standings, 19 points behind 21st-placed Birmingham City.
According to the Rotherham Advertiser, Johansson is likely to depart from Rotherham at the end of the term if they are unable to avoid League One football.
The report claims that the Sweden international's current deal in Yorkshire contains a clause that would make a move away from the Millers easier.
It is understood that there is a release clause in Johansson's terms at the AESSEAL New York Stadium - a stipulation that can be triggered in the event of relegation.
Such a development will be music to the ears of potential suitors for the 25-year-old shot stopper, including Chris Wilder's Sheffield United.
It is believed that the Blades are keen on the five-time international and could make a swoop for his services during the upcoming transfer window.
There could also supposedly be interest in Johansson from on the continent, with the keeper starting his professional career at Hammarby in Sweden over a decade ago.
After putting pen to paper on new terms at Rotherham in January 2023 - whilst the club was still managed by Matt Taylor - Johansson is contracted to the Millers until the summer of 2025.
It is said that the Blades will have to pay a seven-figure release clause to secure the signature of the Swede, who is regarded as one of the Championship's standout keepers.
Wilder's men are set to be short in the goalkeeping department ahead of the 2024-25 term, with veteran Wes Foderingham running towards the end of his deal at Bramall Lane.
Ivo Grbic was signed from Atletico Madrid during the January transfer window, although the Bosnian has only made four Premier League appearances so far due to fitness issues.