El Aynaoui, the fifth seed, rallied to beat Kristian Pless of Austria, 4-6, 6-3, 7-6 (9-7) in the first round. Rusedski, seeded seventh, had a much easier time against Francisco Clavet of Spain, 7-5, 5-3, on the carpet in the northern Italian city.
El Aynaoui captured the Qatar Open title at Doha during the opening week of the year. He also was forced to rally in that final, overcoming Spain's Felix Mantilla in three sets.
Rusedski took the Heineken Open crown on January 12 at Auckland, New Zealand. The British Davis Cup player battled past France's Jerome Golmard to win his 11th ATP title.
Another Moroccan, eighth seed Hicham Arazi, made his way into the second round. He held off Russian Mikhail Youzhny, 7-6 (7-1), 2-6, 6-3.
In other action, Frenchman Nicolas Escude posted a 4-6, 6-3, 6-4 comeback win over Belgian Olivier Rochus; Russian Nikolay Davydenko dropped the opening set before getting past Brazilian Fernando Meligeni, 4-6, 6-2, 6-3; and Bohdan Ulihrach of the Czech Republic outlasted Jarkko Nieminen of Finland, 6-2, 3-6, 6-3.