Which Middlesbrough player from the current squad do you think has the highest ceiling and is the club doing enough to build around them before someone else comes in with a serious offer?

Every season there's a player at Boro who looks too good for the Championship on their best days and the question is always whether the club can hold onto them long enough to benefit from what they become rather than just developing them for someone else. Would love to know who people here think fits that description right now and whether you trust the club to handle that situation well.