The Columbus Crew signed Costa Rican forward year contract Friday, pending receipt of his ITC and 1 work visa.
Vargas, 26, last played for Costa Rican First Division Club Sport Herediano, where he scored 17 goals over the last two seasons.
"Olman is a tall, physical forward who promises to be a great addition to our club," said Crew coach Robert Warzycha. "He has good speed, a good touch and he works extremely hard."
Vargas began his career in 2007 with Carmelita in Costa Rica's Second Division and had 14 goals over two seasons, and later played for Deportivo Saprissa and Brujas F.C. de Desamaparados.
Per club and league policy, no further terms of the deal were disclosed.