Competing for the first time since his semi-final run in Marseille in February, the seventh-seeded Frenchman broke Vatutin five times to earn his 11th tour-level win of the season after 83 minutes.
"It was pretty tough to stop yesterday after the first set. After one night everything is different. It has been a long wait today with the courts. The key today was to focus and be ready to start the second set well," Bonzi said. "I managed to do it and it is a good win for me after a few weeks off."
The World 50 Bonzi, who reached the final in Pune in January, will next play Pavel Kotov. Bonzi’s match against Vatutin was the only singles clash played on Wednesday at the ATP 250 clay-court event due to rain.
Lorenzo Musetti is the top seed in Marrakech, with Daniel Evans seeded second. The Italian Musetti plays Frenchman Hugo Gaston in his opening match, while Briton Evans takes on Australian Alexei Popyrin.