Sunderland have signed defender Leo Hjelde from Championship rivals Leeds United on a four-and-a-half-year deal for an undisclosed fee.
The 20-year-old centre-back has been limited to just three appearances for Leeds this season, and eight in total.
Hjelde joined Leeds from Celtic, having previously been at Norwegian side Rosenborg, and has been on loan to Rotherham and Ross County.
"I'm a ball-playing centre-back, or left-back," Hjelde said.
"I like to get up and down the pitch. I've been at some big clubs previously and this has helped me develop as a player and as a person, but I'm now ready to push on and take the next step.