Duff took Barnsley to the League One play-off final in his one and only full season at the club, but left last week for a job in the Championship.
There are some familiar names in the running to succeed, with former Sheffield Wednesday and Sheffield United managers on the latest odds list.
There is also an emerging candidate and a someone who remains a strong favourite.
Here are the latest odds courtesy of OLBG.
1. Barnsley FC v Plymouth Argyle. SkyBet Championship. Oakwell Stadium. Picture Bruce Rollinson 11 March 2023.
Barnsley FC are without a manager since Michael Duff left for Swansea City (Picture: Bruce Rollinson) Photo: Bruce Rollinson
2. 6. Nathan Jones
Nathan Jones, who was manager of Stoke City and Southampton last season, is out of work since being sacked by the Premier League club. He is currently at 20/1 for the Barnsley job (Picture: Dan Mullan/Getty Images) Photo: Dan Mullan
3. 5. Dave Challinor
The new candidate is Dave Challinor, who led Stockport County to promotion from the National League and to the League Two play-off final. Current odds 8/1. (Picture: Alex Livesey/Getty Images) Photo: Alex Livesey
4. 4. Chris Wilder
Out of work since his short-term contract at Watford expired, Chris Wilder, the former Sheffield United and Middlesbrough manager, is no stranger to working in Yorkshire. Odds 6/1. (Picture: Tom Dulat/Getty Images) Photo: Tom Dulat