Roster moves made by MLB clubs in August are sometimes made with an eye toward post-season roster eligibility and off-season roster flexibility.
With that in mind, here are the 2018 MLB post-season roster eligibility and Draft-Excluded player rules:
MLB RULE 40 POST-SEASON ROSTER ELIGIBILITY RULES
A club's Post-Season Eligibility List is established at midnight (Eastern) on August 31st.
A club's Active List (25-man roster) must be submitted to the MLB Commissioner prior to the start of the first game of each post-season series (Wild Card game, LDS, LCS, and World Series).
A club's Active List can be changed (tweaked) prior to the start of the first game of each series (WC, LDS, LCS, and WS)
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