Brentford have completed the signing of Oldham Athletic defender James Tarkowski on a three-year contract.
As part of the deal the 21-year-old will return to Boundary Park on loan when the window re-opens on 8th February.
Manager Mark Warburton said: "James is a very talented young defender who we have monitored for a period of months.
"He is a good footballing centre-half, he is comfortable in possession and has a good physique.
"James will go back to Oldham for a month when the loan window opens.
"He will come back to us later in the season and is a big part of our plans for the future."