Argentine Franco Squillari provided the shock of the first round at the inaugural Valencia Open by beating second seed Marat Safin 6-4, 5-7, 6-2 on Tuesday.
The left-hander fought back from a break down to take the first set and although Safin managed to pull level in the second, Squillari eventually wore the Russian down with some fine ground strokes to claim a well-deserved victory.
Safin, who had appeared to be finding his form after making the final of last week's Barcelona Open, joins third seed Alex Corretja on the list of major first round victims in the claycourt tournament.
Corretja lost in three sets to Frenchman Anthony Dupuis on Monday.
Top seed Juan Carlos Ferrero did make it through to the second round, but had to work harder than expected in his 6-4, 6-4 victory over fellow Spaniard Guillermo Garcia-Lopez.
Ferrero broke serve early in the first set, but found himself on the back foot as his young opponent responded with some fine stroke play.
The 23-year-old Ferrero, who admitted at the start of the tournament that he was still tired after last week's Barcelona Open, then had to stretch himself to make sure the match did not go to a third set.
Ferrero, who comes from the Valencia region, will now face compatriot Albert Portas, who beat Slovakian Karol Beck on Monday, in the next round.
In Tuesday's other matches Argentine Gaston Gaudio, who is seeded fourth in the claycourt tournament, brushed aside Brazil's Andre Sa 6-1, 6-1.
Gaudio's compatriot Agustin Calleri, seeded five, also moved safely into the second round with a 6-4, 6-0 win over Igor Kunitsyn.
But another Argentine, number six seed Mariano Zabaleta, slipped to a 6-1, 6-3 defeat against Flavio Saretta of Brazil.