No, you have to release a current member of your squad to bring him in, so that part is correct, the good news is, it doesn’t have to be a first team player, usually I release reserves to bring in a new player should that scenario come into play.
All it says is release or sign, and since you bought him from the market, you do not need to pay anymore to get him into your squad since you paid your price getting him in the auctions.
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