What happened: Players on Major League contracts cannot be traded after the cutoff. Clubs can still place players on outright waivers afterward.

Why it matters: Acquisitions must join a club’s 40-man roster or 60-day injured list by noon ET on Sept. 1 to be eligible for postseason play. Contenders have one final window to address roster needs through trades.

What to watch: Roster filings and corresponding 40-man moves will show which additions are finalized.