Undermining

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Home * Chess * Tactics * Undermining

Undermining is a chess tactic where an opponent guard, defending an attacked piece, is captured. While the removed guard itself is usually not en prise and the attacker even has a negative static exchange evaluation, the point is that there is no recapture available to perpetuate the guards defensive obligations, and leaving a former attacked but guarded piece en prise, with a final net gain for the attacker. Those pattern may be considered in quiescence search to encourage capturing pawns and pieces with otherwise negative SEE ...

Sample

... like Rxc7, capturing the lonesome guard of Be6:

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3k4/2n3p1/3bb3/7p/8/8/6P1/2R1R2K w - - 

Counter Sample

If the undermined piece has a Zwischenzug, things are more complicated. Here quiescence has to deal with checks below the horizon, to become aware undermining does not work here ...

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    
    
    
       
      
      
       
        
       
        
     
   ♚    
  ♞   ♟ 
   ♝♝   
       ♟
        
      ♙ 
        
  ♖ ♖  ♔
3k4/2n3p1/3bb3/7p/8/6P1/8/2R1R2K w - - 

See also

External Links

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