Education
He studied in the Colegio Hispano Americano, which belongs to Spanish residents in Chile.
He studied in the Colegio Hispano Americano, which belongs to Spanish residents in Chile.
Playing in the midfield, he retired in 2009, and one year later he became the coach of his long-time team Union Española. In 2015, he became the new coach of Colo Colo, the most popular team in Chile. Unión Española Sierra made his debut in professional soccer with Unión Española on November 1988 against the Universidad de Chile.
After two solid campaigns with Unión Española, Sierra was transferred to Real Valladolid in Spain.
However during Sierra"s short time in Spain, the team had economic problems which caused Sierra to return Unión Española. After more success he made his debut with the Chilean national team
Colo-Colo He then spent three successful years with Colo-Colo, which saw his team capture the championship in all three seasons. Currently Sierra has found his way back to Unión Española making a stop in between to play with UANL Tigres in Mexico for one season.
He captured the Golden Boot in Chile (awarded to the best professional football player in Chile) in 2004 and 2005.
In 1997, it was widely rumoured that then Premier League side Everton manager Howard Kendall had made an approach to bring Sierra to Goodison Park. However for unknown reasons, possibly relating to lack of sufficient capital, Kendall decided to pull the plug on the deal. Return to Unión Española Sierra announced his retirement in December 2008 and accepted the position of manager with his beloved Unión Española, he will continue on the position until the end of the Clausura 2009 tournament.
Sierra was capped 53 times and scored 8 goals for the Chilean national team between 1991 and 2000.
He played four games at the 1998, scoring a goal on a free-kick against Cameroon. Player = Club Colo-Colo Campeonato Nacional (Chile) (1): 2015 Apertura Copa Chile: Runner-up 2015 Unión Española Campeonato Nacional (Chile) (1): 2013 Transición Individual Manager.