Salernitana announced Friday that Ochoa had signed a deal through the end of the season with an option for an extension.
The 37-year-old Ochoa had been playing for America in Mexico. He previously played for Ajaccio, Malaga, Granada and Standard Liege in Europe.
Salernitana needed a 'keeper with starter Luigi Sepe out injured.
Ochoa blocked a penalty from Robert Lewandowski to preserve a 0-0 draw with Poland in Mexico's World Cup opener last month. Still, Mexico didn't advance from the group stage after losing to eventual champion Argentina despite beating Saudi Arabia in its last game.
Ochoa could make his Serie A debut against defending champion AC Milan when the Italian league resumes on Jan. 4. The southern club is 12th in the standings.
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