The fifth-seeded Spaniard was a service break up at 3-2 when Edmund, who is ranked a career-high 40th, quit the match. Edmund had beaten Ferrer on the way to his first-career semifinal appearance in Antwerp last week.
Feliciano Lopez, who won his maiden title in Vienna in 2004, defeated seventh-seeded Lucas Pouille 6-4, 2-6, 7-5 to set up a match against John Isner of the United States.
Also, Viktor Troicki of Serbia converted his only break point in the final set to complete a 4-6, 7-6 (5), 7-5 comeback win over Kevin Anderson of South Africa.
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