Kris Boyd's prolific Rangers career is set to be over before the end of the week - if Birmingham agree to up their £3million offer for the striker.
The Clydesdale Bank Premier League giants confirmed on Tuesday night they were prepared to sell their 25-year-old top scorer to the Coca-Cola Championship club.
Ibrox chairman Sir David Murray told BBC Scotland: "Birmingham have made an enquiry. We talked about money but we haven't agreed a fee and no business will be done today. We rejected a bid of around £3million but if they improve it, we'll allow them to speak to Kris Boyd."
The Light Blues rejected a £2.5million offer from Cardiff before the season started, but reports claim Birmingham will succeed with an offer worth up to £4million.
Boyd has been Rangers' top scorer for three consecutive seasons, including the 2005-06 campaign, despite joining the club on January 1.
He has scored 91 goals for the Ibrox side despite struggling to become a regular starter under Paul Le Guen and Walter Smith.
However, he has enjoyed a lengthy run in the first team this season, especially after quitting the Scotland set-up as he struggled to impress George Burley.
Boyd has netted 20 goals this term from a total of 20 starts and three substitute appearances.
He quickly formed a productive partnership with Kenny Miller, and Smith has made the former Scotland team-mates his automatic first-choice pairing.
Rangers have already sold Daniel Cousin and Jean-Claude Darcheville this season, while summer signings Andrius Velicka and Kyle Lafferty have failed to make a major impact on the first team.
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