Sunderland transfer news: Kristjaan Speakman explains why club have allowed Leon Dajaku to leave on loan

The 21-year-old has made 10 Championship appearances this season, including just two starts, after joining the Black Cats on a permanent deal in the summer.

That came after a clause in the player’s loan deal from Union Berlin was met following Sunderland’s promotion from League One.

The length of Dajaku’s contract has never been disclosed.

Reacting to the move, Sunderland’s sporting director Kristjaan Speakman told Sunderland’s website: “Leon made a positive impact during his first season in England and although he is a versatile forward, our attacking positions are currently occupied by some of our most high performing players.

"At 21 years of age, it is important for a player of his profile to gain regular game time during the second part of the campaign and this an excellent opportunity for him to do that in the Swiss top-flight.

"We wish him well and look forward to supporting his progress from afar.”

Sunderland have already allowed midfielder Jay Matete to leave on loan this month, after the 21-year-old signed for League One leaders Plymouth.

The Black Cats are willing to let players leave on temporary deals if they feel it will aid their development, yet not if it leaves their own squad low on numbers.

Sunderland are still dealing with multiple injury setbacks, with captain Corry Evans likely to miss the rest of the season after suffering damage to his anterior cruciate ligament.