Event = {Back-rank checkmate}
Variant = {white-king-only}
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| r |   |   |   |   |   |   |   |
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|   |   |   |   |   |   |   |   |
+---+---+---+---+---+---+---+---+
|   |   |   |   |   |   |   |   |
+---+---+---+---+---+---+---+---+
|   |   |   |   |   |   |   |   |
+---+---+---+---+---+---+---+---+
|   |   |   |   |   |   |   |   |
+---+---+---+---+---+---+---+---+
|   |   |   |   |   |   |   |   |
+---+---+---+---+---+---+---+---+
|   |   |   |   |   | P | P | P |
+---+---+---+---+---+---+---+---+
|   |   |   |   |   |   | K |   |
+---+---+---+---+---+---+---+---+
b - - (white-king-only)
[start]                 -+<LONG
[1b]                    (1b) Ra1# (#hm=1)
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|   |   |   |   |   |   |   |   |
+---+---+---+---+---+---+---+---+
|   |   |   |   |   |   |   |   |
+---+---+---+---+---+---+---+---+
|   |   |   |   |   |   |   |   |
+---+---+---+---+---+---+---+---+
|   |   |   |   |   |   |   |   |
+---+---+---+---+---+---+---+---+
|   |   |   |   |   |   |   |   |
+---+---+---+---+---+---+---+---+
|   |   |   |   |   | P | P | P |
+---+---+---+---+---+---+---+---+
| r |   |   |   |   |   | K |   |
+---+---+---+---+---+---+---+---+
w - - (white-king-only)
{Black wins}{1 plies}