Barnsley head coach Michael Duff leaves for Swansea City - with Reds search for his successor 'well under way'
He has joined the Welsh outfit on a three-year deal.
In a statement, the Reds said that he was offered an improved deal and contract extension ahead of interest from the Swans.
Club chairman Neerav Parekh said: "As a board, we'd like to thank Michael for all his efforts over the last year.
"We'd also like to appreciate the professional way in which he behaved once Swansea triggered the release clause, and we wish him all the best in his future endeavours.
“We want to reassure fans that the search for a new head coach is well underway and should be confirmed soon in order to make the most of pre-season.
"The foundations laid down at the start of last summer ensure that we're able to compete, and regardless of departures, the club is bigger than any one individual. We promise to continue to build on the positive progress we’ve made and challenge again next season, to push for promotion back to our natural home in the Championship.
The Swans targeted the 45-year-old late last week, with the official completion of Russell Martin’s move to Southampton on Wednesday evening giving them the green light to finalise their move for Duff.
Duff, who took the Reds to the League One play-off final in 2022-23 – where they lost to Sheffield Wednesday less than four weeks ago – will take training for the first time on Friday, with the Swans to head out to a pre-season training camp in Spain on Sunday.
Duff’s departure leaves Barnsley searching for their eighth permanent head coach in the space of just over five years.
Reds CEO Khaled El-Ahmad, added: “We are naturally disappointed to lose Michael after a promising first season in charge, but we wish him all the best for the future.
“As a club, we are prepared for eventualities like these and are constantly reviewing the available opportunities when looking to make an appointment in this position. The recruitment process for our new head coach is well underway.
Duff said: “I’d like to start by thanking everyone from the players to Neerav, Julie Anne (Quay), Jean (Cryne) and Khaled for their immense support during my time at the club.
"I loved every minute of my time at Oakwell, and I take immense pride in the journey we all went on, starting with the loss at Plymouth and all the way to Wembley – the proudest moment of my managerial career so far."