Aberdeen have signed attacking midfielder Ryan Christie on a season-long loan from Celtic, who have snapped up Dons winger Jonny Hayes.
The 22-year-old former Inverness Caley Thistle player spent the second half of 2016/17 on loan at Pittodrie and scored seven goals.
Derek McInnes' men return to action in the second qualifying round of the Europa League on Thursday July 13.
