Otto Strerath

Otto Strerath (* 10. December 1906 in Göttingen , † 5. November 1973 in Hamburg ) was a German composer in chess .

Strerath composed from 1945 to the mid-1950s. In this very short period of time he won many prizes and awards, mainly with two-trainers. He also composed a few threesomes and auxiliary mat tasks. Six two-move tasks were included in the FIDE 1945–1955 album.

Otto Strerath
The Swallow , 1948
82nd themed tournament, prize

	a	b	c	d	e	f	G	H
8th									8th
7th									7th
6th									6th
5									5
4th									4th
3									3
2									2
1									1
	a	b	c	d	e	f	G	H

Mate in 2 moves

Solution: 1. Nh7 – f8 threatens Bd7xe6 mate. Black's first defense idea is to cover the Ne6 under attack. This is possible by any deduction of the rook d5, because this opens the line of action of Ba2 to e6. White can checkmate in four ways on any such deduction, say Rd5 – d1, because the rook opens the white queen's line of move and action to e4 and f3 at the same time: Qb7 – e4 mate, Qb7xf3 mate, Rh4 –H5 mate, g2 – g4 mate.

By deducting the rook on suitable squares, Black can fend off three of the four specified mating moves, so that only one mate remains:

• 1.… Rd5 - d6 (interrupts the line of action of Bb8 after e5 and f4) 2. Qb7 – e4 mate - Qxf3 goes Ke5. Rh4 – h5 fails on Kf4, as does g2 – g4.
• 1.… Rd5 - e5 (interrupts the line of action of Bb8 after f4 and covers the square e4) 2. Qb7xf3 mate . Rxe4 follows Qe4. Rh5 fails on Kf4, as does g4.
• 1.… Rd5 - d4 (covers the squares e4, f4 and g4) 2. Rh4 – h5 mate . Qe4 doesn't work because of Rxe4. Qxf3 + is followed by Rf4. g4 + fails on Rxg4.
• 1.… Rd5 x d7 ( ties the white queen and removes the peg of Ne6) 2. g2 – g4 mate . Qe4 is not possible because of the pin, as is Qxf3. Rg5 + follows Ng5.

This is a secondary form of the (free) stain theme : With the stain theme, the key move itself usually poses a multiple threat, which Black can only differentiate. Here, however, only a mate threatens after 1.Nf8. Only after black Td5 has moved away in any way do all four mates threaten (“secondary”). The four thematic parades of the black rook (Rd6, Re5, Rd4, Rxd7) in turn exclude three of these mates and only allow one.

Web link

• Compositions by Otto Strerath on the Schwalbe's PDB server