Unai Emery reportedly turned down the chance to take over at Everton, causing them to move for Southampton boss Ronald Koeman.
The Celtic striker was in fine form in the Scottish Premiership last season.
Former Newcastle United boss has commented on his former strikers.
Everton failed to finish in the top 10 of the Premier League this past season.
The Ibrox star made his Scotland debut in the 3-0 loss to France last week.
Tottenham Hotspur have been linked with a former wonder-kid.
Leeds United have some very good young players who will be looking to impress their new boss.
Rangers winger Barrie McKay made his debut for Scotland at the weekend.
England boss Roy Hodgson has plenty of options ahead of his side's Euro 2016 Group B opener.
Arsenal made a move for the Leicester City star on Friday.