By Norman Dabell
Montgomerie had put together a solid opening round and needed a birdie on his last hole to lie only four shots off the lead when he three-putted for a bogey to the accompaniment of loud disco music from a nearby tent.
"Is this a party or a golf tournament?," the 46-year-old Briton fumed after signing for a one-under 71 which left him six strokes behind leader Ricardo Gonzalez of Argentina.
Montgomerie, seeking a victory before he leads Europe into battle against United States in October, received support from playing partner Gonzalo Fernandez-Castano.
"I felt sorry for Monty," the Spaniard told reporters. "The music was a bit much. He'd played really well."
Montgomerie had described Fernandez-Castano as a possible candidate for his Ryder Cup team but the Spaniard could only muster a 73, rescuing his day with four birdies in the last five holes.
Gonzalez continued his love affair with Spain and the Real Club course where he won the 2004 Seville Open.
"I love the country, the people, the food, everything, it's like being home," he said after his 65.
"Today I loved the course again. The rough is sometimes like the U.S. Open rough and the key to my round was only going in it three times."
Englishman Waring, ranked 356th in the world, finished up practicing for the Spanish Open at a friend's golf club in the Middle East.
His trip home two weeks ago left him stranded in Dubai, because of the Icelandic volcanic ash problem, until Sunday night.
Argentine Rafa Echenique, Spanish trio Alvaro Quiros, Sebi Garcia and Carlos Del Moral, Swedes Martin Erlandsson and Mikael Lundberg, Irishman Damien McGrane and Britons Simon Dyson and Danny Willett all shared third place on 68.
(Editing by Tony Jimenez)