Matteo Mannasero equalled the course record with a 64 and leads the Andalucian Open after the opening round.
The young Italian has a three-stroke lead and lies on eight-under, ahead of a group that includes Swede Niclas Fasth, English duo Anthony Wall and qualifying school graduate Lloyd Kennedy, South African Open champion Hennie Otto and Spain's Eduardo de la Riva.
Six players are four shots behind Manassero, including Canadian Mike Weir, trying to rebuild his career after elbow surgery, and Pablo Larrazabal.
Damien McGrane and Michael Hoey lead the Irish challenge on three under while Shane Lowry is two shots further back with Simon Thornton and Gareth Maybin on level par.
Peter Lawrie, however, had a day to forget and lies 14nd in the 144-strong field after a six over round of 78.