The Spaniard is set to link up with former boss George Burley at St Mary's
Idiakez will also link up with former Rams Striker Gregorz Raziak, who is finding his form he used to show for Derby County in recent games.
Derby County, as first brought to you on this site a few weeks ago look favourite to add another defender to their ranks in the form of Andy O'Brien. The Republic of Ireland International looks set to move from Premiership Portsmouth.
O'Brien made his name at Bradford and then Newcastle United and the 27 year old has had several high value moves in the past and Portsmouth turned down a £1.5million move for the defender only last month.