Almanza ran internationally from a young age, coming fourth at the 2009 World Youth Championships in Athletics before taking the 800 m title at the Pan American Junior Championships. She won at the Barrientos Memorial in March 2010 and followed this with a personal best of 2:03.03 to take the silver medal at the 2010 Ibero-American Championships in Athletics. She ran a national junior record of 2:02.04 in Havana in July and came fourth at the 2010 World Junior Championships in Athletics.