Herbie Kane injury blow for Barnsley FC plus updates on Aaron Leya Iseka and Clarke Oduor ahead of Plymouth opener
Kane, who spent last season on loan at Oxford United - with hopes abound that he can be a big player for the Reds this term - has been struggling with a groin issue, which also afflicted him at the end of 2021-22, while at Oxford.
Better news sees Clark Oduor and Aaron Leya Iseka back in the fray for the opening-day trip to Plymouth Argyle, having missed the final pre-season friendly at Sheffield United.
Duff, who said the club are not close to finalising any new signings ahead of the weekend - with no players also likely to go out - said: "With Herbie, I think we are looking at five to six weeks.
"It is not as bad as we first feared because we thought it might be an operation. It's unfortunate as has done his pre-season and he is almost going to have to do another pre-season now to get him fit. He's a good player and proven at this level..
"When he is on the pitch, he will impact the pitch, no doubt.
"Liam Kitching had a bit of a dead leg from the weekend, but should be okay. Micha (Michal Helik) is a bit short of minutes. Jordan Williams is short on minutes, but we have got to go with what we have got.
"Clarke and Aaron are back in after a full weeks' training and back in the fold."