The last minute re-broadcast of the Superfight between Marvin Hagler vs. Sugar Ray Leonard messed with the schedule

The 3:30 pm re-broadcast of the Superfight between Hagler and Leonard was a last minute change that replaced a scheduled airing of the film Head Office. The schedule for the rest of the night was also changed, according the April 18th, 1987 listing in The New York Times.

Here's the original schedule as it appeared in the HBO Guide before the change:

April 18

Saturday

10:00 PMOn Location:® Sam Kinison
11:00 PMThe Hitchhiker "Made for Each Other"
11:30 PMHead Office (1985) (PG-13) (CC)
1:05 AMGhostbusters (1984) (PG) (CC)
2:55 AMAlamo Bay (R)
4:40 AMAfter Hours (1985) (R) (CC)

In addition to changing the order of the late-night programming, the debut of Sam Kinison's special was inexplicably replaced by Steven Wright's On Location.