D.C. United has finalized the acquisition of attacker Lucas Rodriguez from Argentine club Estudiantes, a one-year loan with an option to purchase next winter. To acquire his Major League Soccer discovery rights, United sent $50,000 in general allocation money to Atlanta, which had first taken interest in the 21-year-old midfielder. Rodriguez promises to bolster an already formidable attack, led by Luciano Acosta and Wayne Rooney, and add to an Argentine-seasoned midfield. Acosta, the playmaker, is coming off his finest season in Washington and United is attempting to retain countryman Yamil Asad, who was on loan from Argentina’s Velez Sarsfield in 2018. (The club is optimistic of striking a deal.) In theory, Ben Olsen could start the three Argentines in a line behind Rooney, the English striker who revived the organization last summer. The undisclosed loan fee, one source said, would go toward the price of purchasing Rodriguez’s contract, a transfer that could cost more than $3 million. His international value is listed at about $3.7 million. Despite his age, Rodriguez has played regularly in the Argentine first division, starting 53 league matches the past 2½ seasons and 12 Copa Libertadores games over two years. He also started for Argentina at the 2017 Under-20 World Cup in South Korea.