Dundee have signed Mark O'Hara on a two-year deal from Kilmarnock.
The 20-year-old becomes Paul Hartley's fourth signing of the summer after Inverness CT pair James Vincent and Danny Williams and Dutch striker Yordi Teijsse.
Hartley told the club website: "He is a player that fits the bill perfectly. Mark is at the right age and is someone we think we can work with and develop. He can play right-back but we want to develop him in the middle of the park."