Rangers are running out of time to trigger a cut-price deal for Czech talisman Vaclav Cerny . Record Sport can reveal the Ibrox club have an option to sign Cerny for a sum of around £5.5 million as part of the original agreement thrashed out when they secured the player on a season-long loan from Bundesliga outfit Wolfsburg. But that fee is expected to soar if Cerny is put up for sale on the open market on the back of a spectacular first season in Scottish football. And that means incoming American owner Andrew Cavenagh and his US consortium might have to rush into action while they wait for lawyers to rubber-stamp their multi-million pound takeover proposals. Cerny’s arrangement will expire before the end of the current campaign unless the Germans receive a cast iron bid to guarantee the funds. It’s understood the deadline will kick in before the end of May - which gives Rangers just a matter of weeks to confirm whether or not they intend to stump up in full for the 27-year-old. It’s expected health insurance tycoon Cavenagh and his cash rich partners from the San Francisco 49ers will conclude their buy-out of a majority holding of more than 50 per cent before the end of next month. But they have already been made aware of the urgency around Cerny’s contractual situation. Wolfsburg - and Cerny’s agents - have also been made aware of growing interest from a number of clubs across Europe, all now closely monitoring developments. And, if Rangers can’t or won’t match the agreed fee, it’s anticipated Cerny’s price tag could more than double when the transfer market opens for business and those would-be bidders are free to enter the race for his signature. Cerny’s stock was further enhanced on Wednesday night when he scored a stunning long range opener and turned in a man of the match performance for his country in a World Cup qualification romp over Gibraltar. And he appears to be flourishing for Rangers under the instruction of interim management of Barry Ferguson who has deployed him in a more central attacking role since taking over from sacked Philippe Clement. He has contributed a total of 17 goals and seven assists in 44 appearances since making the switch last summer. During the international break, in an interview with the media in his homeland, Cerny revealed he hopes to extend his stay in Glasgow on a longer term basis. Asked if he hopes to make the move permanent he replied: “I definitely do. But there are so many aspects that I can’t control. All I can do is be the best I can and keep up my form and numbers.” Tune in to Hotline Live every Sunday to Thursday and have your say on the biggest issues in Scottish football and listen to Record Sport's newest podcast, Game On , every Friday for your sporting fix, all in bitesize chunks.