[Editor’s note: This story has been updated with information from MLB’s official report.]

In the most dramatic ruling of his five-year tenure, baseball commissioner Rob Manfred came down hard on the Astros Monday for illegally stealing signs during their World Series championship season in 2017.

The unprecedented penalties are Manfred’s response to the damage the Astros inflicted on the sport’s integrity, and should serve as a powerful deterrent to any team that engages in such conduct in the future.

The penalties, according to sources with knowledge of Manfred’s decision, include:

• A one-year suspension for general manager Jeff Luhnow.

• A one-year suspension for manager A.J. Hinch.

• The forfeitures of first- and second-round draft picks in both 2020 and ’21.

• A fine of $5 million, the maximum allowed under MLB’s constitution.

• The placement of former Astros assistant GM...