Swansea City legend Alan Curtis believes keeping Graham Potter must be the club's priority this summer.
Daniel James is among a host of Swansea players who could attract interest from rival clubs.
But Curtis, who will retire from his role on the club's coaching staff next month, says Potter is the one man who must not leave.
"The crucial thing at the moment is that we have to keep Graham," Curtis told BBC Sport Wales.
"He has brought things out of the players and a style that maybe they didn't think they had.
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"It would be brilliant if we can keep this squad together. I am not sure whether it's going to happen, but the club has always lost players going back to Ivor Allchurch, Cliff Jones and Terry Medwin.
"If Graham stays, it's such a young, exciting team that is only going to get better.
"He has certainly improved them as players. I think he is the big key to what we are going to look at next season."
Swansea have rebuilt in 2018-19 having seen their seven-year spell as a Premier League club end last May.
Despite losing a raft of senior players as Swansea have cut costs, Potter has built a vibrant young team who have played some superb football.
They have a chance of reaching the Championship play-offs - they are five points adrift of the top six with three games to play - but regardless of what happens this season, Curtis wants Potter to stay for the long term.
Potter signed a three-year deal when he joined Swansea last summer but his work at the Liberty Stadium is unlikely to have gone unnoticed elsewhere, with Celtic already linked with to the former Ostersund boss.
"I know he loves the club, he loves the area and he loves the environment he works in, so he has got everything he needs for him to develop," Curtis added.
"He is still developing as a manager. I think he feels this is the right place for him. Brendan (Rodgers), Michael (Laudrup) - they fitted (Swansea) hand to a glove - and I think Graham feels the same way.
"I hope he stays and I hope we can develop. It will be brilliant if we can get into the play-offs and go back up this year, but if not I certainly think we can challenge next year if Graham is given the right tools."