Predicting Players Who Will Break Out into Stardom in 2015 Playoffs

October has a way of defining careers. Over the next few slides, we'll identify a handful of MLB players who seem poised for a breakout during postseason play.

The definition of what constitutes a breakout star will vary, but each player on this list has at least flashed some sort of top-tier quality in his career. More than a few are hurt by the shadow of more talented teammates, while some are still too young to have made much of an impact.

Can Travis d'Arnaud stay healthy and put together a quality month for the New York Mets? Starling Marte and Addison Russell are often overlooked in favor of their teammates, but each is capable of changing a postseason series. Elsewhere, Luis Severino…