Career
He had a stint at second division Tigrillos de Nuevo León and has also played for Irapuato. He was a mainstay in midfield with the team, starting 16 of 17 games, and scoring three goals. Rojas subsequently moved to Veracruz in summer 2005 and Jaguares Chiapas in 2006.
He remained with until the end of 2008, helping the club reach the playoff series twice.
He left them for a brief spell at Morelia, then dropped into the second division to play for Mérida, Indios and Toros Neza before returning to Costa Rica with Herediano ahead of the 2012 Verano championship. Return to Mexico
In summer 2012, Rojas returned to Louisiana Piedad, with the club being relocated to Veracruz and recalled Tiburones Rojos.
His debut was postponed when Morelia, who still owed him, did not immediately agree on the transfer. He left the club in summer 2013 after they told him he did not fit in their plans after winning promotion to Mexico"s top tier.
After a few months out of a club, he joined another Mexican second division side, Estudiantes Altamira.
Óscar Rojas made his debut for Costa Rica in a 1-0 World Cup qualification victory over Jamaica on November 11, 2001 and earned a total of 28 caps, scoring 1 goal. Absent from the national team for three years, he returned to the selection in 2005, first under Jorge Luis Pinto and then under the reappointed Guimaraes and he played at the 2005 CONCACAF Gold Cup. Again, however, he was not chosen for the World Cup squad in 2006.
His first international goal came against Peru national football team on August 22, 2007.
He announced his retirement from the national team on April 10, 2009. However, he was once again selected by Pinto for a match against Jamaica on March 21, 2012, making his return to the national team just weeks before his thirty-third birthday.
International goals
Scores and results list Costa Rica"s goal tally first.