Sunderland boss has this clear Charlie Wyke message as he responds to recent transfer speculation amid Nottingham Forest, Millwall, Middlesbrough and Cardiff City links

The 28-year-old reached 30 goals in all competitions for the season with a brace against Accrington Stanley last week, and is attracting interest from a number of clubs ahead of his current deal expiring at the end of June.

Nottingham Forest, Millwall, Middlesbrough and Cardiff City have all been linked with a move for the forward, who has been an utterly integral part of Johnson's side since his arrival.

Johnson is not involved in contract negotiations, which fall under the remit of Sporting Director Kristjaan Speakman.

He nevertheless hopes that when the time comes, Wyke will be eager to continue his development on Wearside.

"The contracts is more one for Kristjaan Speakman," Johnson said.

"As far I'm concerned you're maintaining the player-coach relationship. That's the key.

"Of course I'd love to work with Charlie Wyke next season, but whether that's possible or not I haven't got all the answers for you.

"At the same time, what Charlie has got is a coach who trusts and believes in him, and with the coaching staff and his team-mates, have got him into a position where he's currently second top scorer with lots of different types of goals.

"My favourite goal was the second one against Accrington Stanley where he peeled into the blindspot and then nipped across the near post to score, because of the amount of work we and he have done on that, and the timing of it all.

"He's improved as a player over the course of the season, there's no doubt about that.

"I think he's grateful for that and hopefully that will stand us in good stead when the club is ready to sort of challenge for his contract."

Sunderland have a raft of players out of contract in the summer, with Speakman saying in February that all players would have a chance to prove they have a future under Johnson.

He has been working on two squad composition models, dependent on whether or not Sunderland achieve promotion back to the Championship.

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