Derby County boss Wayne Rooney has accused Crystal Palace and other clubs of taking advantage of the Rams' financial situation in the January transfer window.
The Eagles plucked teenage striker Luke Plange from Pride Park on deadline day for a reported fee of £1million but have sent him back on loan to the club for the remainder of the season.
Derby also lost 18-year-old left-back Dylan Williams to Premier League side Chelsea, who had only made nine first-team appearances for the club before departing this month, and lost experienced full-back Graeme Shinnie to Wigan.