Derby have signed Sheffield Wednesday striker Sam Winnall on loan in a swap deal for midfielder Jacob Butterfield.
The Rams have also signed Birmingham midfielder Maikel Kieftenbeld, 27, for an undisclosed fee on a two-year deal.
Winnall will spend the rest of the season at Pride Park, with Butterfield also moving on a season-long deal.
Former Wolves trainee Winnall, 26, has scored four goals in 18 games for the Owls since joining from Barnsley for an undisclosed fee in January.
Butterfield, 27, joined Derby from Huddersfield in September 2015 and has since made 89 appearances.
Both Winnall and Butterfield will be unable to play against their parent clubs during their loan periods.
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