The 25-year-old has been a standout performer at the AESSEAL New York Stadium this season despite the Millers failing to retain their Championship status.
Under a mixture of Matt Taylor, Leam Richardson and Steve Evans, Rotherham have earned the title of whipping boys in the division, winning only four of their 45 league fixtures so far.
Therefore, the Millers sit rock bottom of the second-tier standings, 24 points behind Neil Dewsnip's Plymouth Argyle in the relative safety of 21st heading into the final weekend of action.
Despite a woeful campaign on a team level, Johansson has kept five clean sheets in Championship matches for Rotherham, who are now preparing for life back in League One following a two-year absence.
Leeds, Stoke keen on Rotherham's Johansson?
According to the Sheffield Star, two Championship clubs have joined the pursuit of Rotherham keeper Johansson ahead of the summer transfer window.
The report claims that Premier League-chasing Leeds United are admirers of the Swede, who has made a single appearance for his national side so far.
Looking to climb the Championship standings in 2024-25, Steven Schumacher's Stoke are also said to be keen on Johansson, with the 25-year-old set to leave this summer.
The shot-stopper is not expected to stay at the New York Stadium for a League One campaign, with Rotherham boss Evans admitting that his first-choice keeper is likely to leave this summer due to "huge interest".
As a result, the Millers coach focused on the future on Saturday afternoon when they travelled to Bristol City, starting Dillon Phillips in between the sticks at Ashton Gate.
Sheffield United's goalkeeping situation
Sheffield United were heavily linked to a move for Rotherham's Johansson during the January window, when Chris Wilder was attempting to recruit the correct personnel to keep the club in the Premier League.
A switch for the Sweden international never materialised, though, with the Blades reportedly having concerns over the keeper's distribution capabilities.
There is understood to be a release clause of an initial £750,000 in Johansson's contract with the Millers which United would be smart to trigger.
January signing Ivo Grbic has struggled with a mixture of fitness and form issues so far at Bramall Lane, whilst Wes Foderingham's deal expires at the end of the campaign.