Millwall boss Kenny Jackett is expecting winger David Martin to leave the club next week when the loan window opens.
Martin is out of contract at the end of the season and has so far declined the opportunity to sign an extension at The Den.
The League One club accepted a £200,000 offer from Derby County before the close of the transfer window, but the deal was unable to be completed before the deadline.
Derby manager Nigel Clough still hopes to sign Martin on loan and Jackett confirmed the 24-year-old will not feature for Millwall against Norwich City on Saturday.
"The deal couldn't be completed time wise by 5pm on Monday, there just wasn't enough time and these things happen," Jackett told the News Shopper.
"For whatever reason, everything that needed to be completed unfortunately couldn't be done.
"We reluctantly accepted the bid because we haven't been able to get Dave to sign a new contract this year, so unfortunately halfway through the season we have to take what we can because we would lose him for nothing in the summer.
"From our point of view there is an offer of a contract on the table for the player.
"It obviously hasn't been accepted and he isn't going to sign it, so the next thing is after that if there is a bid then reluctantly we will take it.
"Dave will not be involved in the Norwich game."