Gary Irvine has won a one-year contract extension to stay at Dundee as fellow defender Kyle Benedictus exited for Raith Rovers.
Irvine joined the Dens Park club in 2010 after leaving St Johnstone and the Bellshill-born 30-year-old made 30 appearances this season.
Benedictus becomes Rovers' second signing in a week after the arrival of striker Mitch Megginson from Dumbarton.
The 23-year-old came through the youth ranks at Dens Park.
However, he only made 22 first-team appearances and spent most of last season on loan to Rovers' Scottish Championship rivals Alloa Athletic.
Benedictus, who made 34 appearances for the Wasps, helped Alloa avoid relegation after a play-off victory over Forfar Athletic.
The 22-year-old Megginson, who began his career with Aberdeen and had loan spells with Arbroath, Brechin City and Alloa, joined Dumbarton in 2013 and scored four goals in 40 appearances last season.