A consortium led by former Rangers director Paul Murray lodged a formal bid for the stricken Glasgow giants on Friday, subject to approval from creditors.
The Blue Knights consortium and Brian Kennedy, owner of English rugby's Sale Sharks, have joined forces to table a "substantial" written bid for the club, which went into administration earlier this season.
The offer is subject to a Company Voluntary Agreement (CVA) being accepted by creditors as well as the securing of current owner Craig Whyte's shares.
"We are pleased to announce that the Blue Knights, led by Paul Murray and Brian Kennedy, have joined forces and at 3pm today have submitted a written offer to the lawyers of the administrators to purchase Rangers Football Club," statement from the Blue Knights and Kennedy said.
"This offer we consider to be substantial and is conditional on a CVA being approved by the creditors, and Mr Whyte's shares being acquired.
"We hope this is accepted so that we may proceed with due diligence forthwith and make a start to the task of rebuilding Rangers Football Club of 1872."
Administrators were called in to Rangers on February 14 after British tax authorities went to court to seek payment of an unpaid bill that had built up since Whyte took charge at Ibrox in May.
Entering administration meant Rangers were docked 10 points -- a move that effectively handed this season's Scottish Premier League title to arch Glasgow rivals Celtic, recently crowned champions.