Lee Johnson admits releasing young striker Rhys Oates was the hardest decision after he let six players go and put two on the transfer list yesterday in an effort to 'put my stamp on the club'.

Strikers Oates, Leroy Lita, Kane Hemmings and Nana Boakye-Yiadom have all failed to win new deals as have centre-backs Jean Yves M'voto and Martin Cranie – the club's highly-paid captain. James Bailey and Milan Lalkovic have both been placed on the transfer list.

The only player to have officially been offered a contract is 19-year-old striker George Maris – a one-year deal– while the club are 'in dialogue' with centre-back Lewin Nyatanga and are expected to offer a two-year deal.

Oakwell academy graduate Oates was the surprise exclusion from the retained list after Johnson praised him for an impressive substitute appearance in the 5-0 final day win over Rochdale on Sunday in which he set up a goal.

The 20-year-old told the Chronicle: "I am very upset. I have been at Barnsley for 14 years. I was told it was undecided before the match on Sunday and I thought I played really well so I was a bit surprised to be released. I will try to get another club and prove people wrong but I do have good memories of Barnsley."

Johnson admitted the release of Oates – who has made ten appearances off the bench for Barnsley– was the most difficult decision to make. The Reds' head coach told the Chronicle: "I can understand why supporters would be surprised by the Rhys Oates decision.  It was the toughest one to make.  He's a good young player and he did very well on Sunday. He came on at 0-0 and we won the game 5-0.

"But I want to bring in three players in his position for next season and they will probably jump ahead of him. Rhys wouldn't play many games for Barnsley next season so it wouldn't be ethically right to keep him.

"All the players who have been released have given their best to the club and I wish them well but I have to free up room to put my stamp on the club.  I want my team to have an identity and they don't fit into that. It doesn't mean they are bad players and they might flourish in someone else's team."

Bailey, who signed last summer, and January arrival Lalkovic are contracted until 2016 but have not played regularly since Johnson arrived in February and are 'available for immediate transfer'.

Johnson said: "They are good players but they don't quite have the characteristics we require. "Those two probably won't get many games next season if they stay. I don't think they will have any problem in getting a new club."

The only regular starter to be released is Cranie who has played 123 games for the Reds across the last three seasons. He is understood to be one of the best-paid players in League One and the Reds would have needed him to take a huge paycut.

Johnson said: "Martin Cranie is on a good Championship contract and rightly so because he's a very good player. But we didn't feel we could get near renewing it in League One.

"We didn't even enter negotiations with him. He's been here a long time and he needs a fresh start. "Other players fit a different profile that we are looking at and we don't want to block the progress of someone like Mason Holgate. I have enjoyed working with Martin and I don't think he will have any problem finding a new club."

Academy scholars Bailey Gooda, a centre-back, and left-back Matty Templeton have been offered professional deals.