Millwall have signed Ryan Leonard from fellow Championship side Sheffield United on an initial loan deal.
The 26-year-old midfielder will make his switch to The Den permanent in January after the Lions agreed an undisclosed fee with the Blades.
He has agreed a "long-term" contract with Millwall and will become their club-record signing.
Leonard has featured 17 times for United after moving to Bramall Lane from Southend United in January.
However, he is not eligible to make his debut for the south London against Swansea on Saturday
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