"We needed some reinforcements and Anelka will fill a gap. He will sign a five-month contract with an option for a second year if the circumstances are right," Marotta told Sky Sport 24.
"In this market, expectations are high but supplies are limited, which is why we are pursuing these types of transfers. Anelka will join an attack where Giovinco and Vucinic are playing with consistency. Matri and Quagliarella are available but they are not in optimal condition since they have not played official matches for a few weeks.
"Anelka is a temporary reinforcement because he has a contract for five months."
Although Marotta admitted that the 33-year-old Frenchman was unlikely to be more than a stop-gap for the Italian champions, he hinted at some summer signings - with Bebeto's son Mattheus possibly amongst them.
"We will make important investments in July. We could have spent money this month but we have to be shrewd and rational.
"Bebeto['s son]? He is an important name but he was only born in 1994 so it will take time to fully understand his qualities. We have not signed him yet."
The 18-year-old, currently of Flamengo, impressed at the South American Under-20 championship in Argentina and would present a forward-thinking signing for La Vecchia Signora.