Pinned piece unpinned and pinned again 1

This is the first special example file for the 25th TT CCM C 5.5.2009.

Having decided the theme of the tourney, I was looking for examples. Actually I have found it more difficult to look for problems showing the theme than usually. While in helpmates it is quite often the part of the content, it has no specific name to look for. In twomovers there is no systematic terminology either, but at least there is a couple of themes named after composers with specified pins related content. I have started a discussion thread at the Mat Plus discussion board. Please, contribute there is something to say in relation to the following set of orthodox twomovers or theme of the tourney in general.

The definitions below are taken from the WinChloe documentation.
Marcel Segers
1st Prize La Scacchistica di Roma 1936

1.Rxc3? th. 2.Qe4#
1...Bb1 2.Se5#
1...Bd5!

1.Kxg7! th. 2.Se5#
1...Qc7 2.Qe4#
1...Rxg5+ 2.Sxg5#
1...Re7 2.Qf6#
1...Bxf7 2.Rxf7#

This shows (in the first variation) Castellari theme: The key selfpins a piece A (wQ) and selfunpins a piece B (wSf7) which threatens to mate. The defence (1...Qc7) repins B and unpins A which mates.

Moreover, the variation 1...Re7 is thematic for out TT as well, as wSf7 is repinned again. Thus together we have two thematic variations with the same piece in various pin states.









#2 (11+7)
Aligi Lenassi
4th Prize e.a. Volksgazet 1953

1.Qb6! th. 2.Qe3#
1...Rd4, Bf4, Sf5 2.Sc3#
1...Bd4 2.Qc6#
1...Sd5 2.Sd6#
1...Rd3+ 2.exd3#

Servais theme here: The key is made by B (wQ) which indirectly selfunpins A (wSb5) and unpins a (bBe5). In a defence (1...Sd5), a indirectly selfpins b (bSe7) and A or B mates (here A - wS) using the pinning of b and indirectly selfpins B or A (here B - wQ). In another defence (1...Bd4), b indirectly selfpins a and A or B (the one which has not mated in the previous variation) mates using the pinning of a.

For theme tourney, however, two variations with knight defences are important. They cause the pin of Be5 that was unpinned in the key.









#2 (12+9)
Pierre Monreal
Francois Michel
2nd Prize Gazeta Czestochowska 1967

1...Rxc5+ 2.Rxc5#

1.d5! th. 2.Qxf2#
1...Rxd5 2.Sd4#
1...f1=Q 2.Rxf1#
1...g5 2.S4g3#
1...Rxe4 2.dxc6#

Anti-Rupp theme: The key selfunpins a piece A (wQ) and unpins a piece a (bRe5).

The defence (1...Rxd5) pins A and selfpins a.
For the 25th TT CCM, two variation with bR selfpin are important.









#2 (10+9)
Sergej Fedyakov
1st Prize Kudesnik 1991

1.Rxd4! th. 2.Qe8#
1...Bxd6 2.Re4#
1...Sexd4 2.Sf4#
1...Bxd4+ 2.Sxd4#

Hassberg theme: The key selfpins A (wRe4) and unpins a (bBe5) which directly selfpins and unpins A which mates.

It is shown in the first variation, and the second variation would be thematic for the 25th TT CCM as bB is indirectly selfpinned by knight move. The scheme is similar to that of Lenassi's #2, what is probably not so surprising given the limited number of working mechanisms for similar themes.









#2 (8+11)
Yves Cheylan
6th HM The Problemist 1996

1...Kf5 2.Sxe7#

1.Sg3? th. 2.Qxe7#
mais 1...Bc5!

1.Sd6! th. 2.Qxe7#
1...Qxd6 2.Sxe7#
1...Qxd5+ 2.Re4#
1...Qc4 2.Sc7#
1...exd6 2.Qf6#

Again Hassberg theme, but also the most rich from the quintuple of problems in this file from the point of view of the 25th TT CCM. The key unpins bQ which is then pinned again three times! 1...Qxd6 selfpins the queen directly, in as does the 1...Qxd5+ defence too. 1...Qc4 is the most interesting variation with masked pin turned into real by knight jumping away.

I am sure this might be more than imitated in fairy twomover.









#2 (8+7)

Comments to Juraj Lörinc.
Back to main page of Chess Composition Microweb.