Sheffield United have signed Derby pair Jayden Bogle and Max Lowe and sealed a loan deal for Chelsea's Ethan Ampadu.
The wing-backs have both signed four-year deals at Bramall Lane and move for an undisclosed combined fee while Wales international Ampadu will spend the season on loan.
Chris Wilder told the club website: "The Championship has been a great recruitment area for us and I wanted to bring some young players in who will provide competition for places.
"Jayden and Max will put huge pressure on George (Baldock) and Enda (Stevens).
"It was important we got the right characters, the right type of players, ones who are athletic and technically very good, both are modern-day wing-backs and I'm looking forward to working with them."
Regarding Ampadu, he added: "Ethan is an outstanding young player for Chelsea, and we've worked really hard to get his signature for the season.
"It's an important season for Ethan and playing in the Premier League for us is a good move for everyone. He brings a lot of qualities to the group and he's someone we've tracked for two or three seasons."
The 19-year-old joined the Blues from hometown club Exeter in 2017 and has since won 13 caps for Wales, the land of his mother's birth, as well as spending last season on loan with Bundesliga side RB Leipzig.
Bogle, 20, had spells at Reading and Swindon before moving to Derby as a youngster in January 2016. He was promoted to the first team for the 2018-19 season and went on to make 50 appearances.
Lowe, aged 23, was a product of the Derby academy and recently had a successful loan spell at Aberdeen.
Wilder added: "We've got a clear plan and identification of what we need and we're still going through that process. We're not just signing players because other people are in for them, we're signing these players because they fit into what we are about.
"It's game on for everyone, it's not a warning, it's a fact and yet again I have to thank the board for making the two permanent signings happen because it's a great bit of business for the football club."