Usually a trial run for rookies, MLB‘s September roster expansions have instead become a portal for second chances.

Prominent prospects are now typically promoted before the final month, especially if they can help a contender. In years past, Alex Bregman, Gary Sanchez and Jameson Taillon might have debuted as September call-ups.

Now it looks like they should have arrived sooner.

Outside of Yoan Moncada, who has quickly proven too raw for a grand stage, no star youngster has began his MLB career this month. In most cases, the most notable call-ups are working their way back into good graces after an earlier demotion.

Regardless of their journey to the majors, the following players can impact the playoff picture and earn a postseason roster spot.

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