Has an NPB (Japan) game ever ended 28-5?

Exactly once. On October 17, 1950, Taiyo Whales beat Chunichi Dragons 28-5, and no NPB (Japan) game before or since has ended that way. When it happened it was a scorigami, the first 28-5 in league history.

Where 28-5 sits among nearby NPB (Japan) scores. Deeper blue means a score has happened more often; the outlined cell is the new one.

That makes 28-5 the 191st most common final score out of 223 that have ever occurred in NPB (Japan). One point away, 29-5 has happened never and 28-6 has happened never.

Every 28-5 in NPB (Japan) history

Date	Result	Season
1950-10-17	Taiyo Whales over Chunichi Dragons	1950

Open the NPB (Japan) grid at 28-5