Millwall have allegedly tabled a club-record bid to sign Ben Marshall from Wolverhampton Wanderers on a permanent basis.
The winger spent the latter half of last season on loan with the Lions and, according to Sky Sports News, they have submitted an offer of £1.25m to keep him at The Den.
Wolves are said to be open to selling Marshall, and Millwall are his preferred destination following last season's successful loan.
The 27-year-old scored three goals in 16 appearances while at Millwall and helped them to an eighth-place finish in the Championship last term.
Millwall last broke their transfer record in 1989 when they signed Paul Goddard from Derby County for £800,000.