The 25-year-old outfielder is regarded as an excellent defender and he hit .285 in 374 games in the Cuban League before defecting in 2015. Because of political reasons, Heredia hadn't played competitive baseball since 2014 until signing with Seattle. As a 21-year-old with Matanzas in the 2011-12 season in Cuba, Heredia hit .343/.439/.527 in 443 plate appearances and won a Gold Glove Award in center field.
With right fielder Nelson Cruz dealing with a sore foot that caused him to miss Wednesday's series finale in Pittsburgh, Heredia gives the Mariners an extra outfielder as well as a late-inning defensive and pinch-running option.