A one-club man, Moscoso has come through the youth categories at
FAS and played for the reserves before making his professional debut in July 2004 against
Once Municipal. With FAS Moscoso he had a very successful period, winning two national league titles:
Clausura 2005 and
Apertura 2009, in this last tournament Moscoso was the hero of the final when he scored important goal in the minute 97 against
Águila in a 3–2 victory. However, with FAS he also lost the finals of the
Clausura 2006,
Apertura 2006,
Apertura 2007,
Clausura 2008,
Clausura 2011,
Clausura 2013 and
Apertura 2013. In 2015, however, Moscoso signed for
UES. With UES Moscoso had a very irregular performance in the two seasons that he spent with the team. The situation of UES, which was in danger of descent and with administrative problems, did not help either. In 2017 Moscoso returned to sign for FAS. At the end of the same year, Moscoso received a tribute from the club in the
Estadio Óscar Quiteño, recognizing his loyalty and his time of stay with the club of
Santa Ana, prior to a game against
Santa Tecla. ==International career==