American Robert Sarver has bid £18m to buy a controlling stake in Rangers, according to reports.
Sarver, who also owns the Phoenix Suns basketball team, submitted his offer shortly after Christmas but is unlikely to succeed, according to BBC Sport, as other investors continue to buy shares.
Sarver is said to have also submitted his bid to WH Ireland, which manages Rangers International Football Club's listing on the Alternative Investment Market, and is now open to working with both fans' groups and other investors, after seeing that it is highly unlikely that he will be able to buy 100% of the club.
The 52-year-old is also chief executive officer of Western Alliance Bancorporation, and he is described as "a serious player with superb credentials".
Rangers currently lie second in the Scottish Championship.
