What happened: Players on 40-man rosters can be traded until the window shuts. Minor leaguers outside those rosters remain eligible to be dealt afterward.

Why it matters: The cutoff is the final opportunity for contenders to reinforce their rosters through trades. Players may still move through outright waivers after the deadline, but the former waiver-trade system is no longer available.

What to watch: Watch for completed deals before 6 p.m. ET and the corresponding roster moves that follow.