In the day's only two main draw matches, Robredo, a former world No. 5, bested France's Guillaume Rufin 7-6 (7-2), 6-4, and Kavcic dispatched Moroccan wild card Mehdi Ziadi 6-2, 6-4 on the clay courts at Complexe Al Amal.
Kavcic now goes on to play top-seeded Stanislas Wawrinka in the second round.
Two-time defending champion Pablo Andujar will open play Tuesday against qualifier and fellow Spaniard Pablo Carreno-Busta.
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