diff --git a/libgdx/core/src/com/mountainreacher/chess/model/ClassicBoard.java b/libgdx/core/src/com/mountainreacher/chess/model/ClassicBoard.java
index 7efdb54..c7ee55b 100644
--- a/libgdx/core/src/com/mountainreacher/chess/model/ClassicBoard.java
+++ b/libgdx/core/src/com/mountainreacher/chess/model/ClassicBoard.java
@@ -129,8 +129,9 @@ protected Piece kingIsInDanger(int kingTeam, int row, int column) {
 
                 // Closeness with the other king
                 if (piece.getFigure() == Piece.KING) {
-                    if (Math.sqrt(Math.pow(piece.getRow() - row, 2)
-                            + Math.pow(piece.getColumn() - column, 2)) < 2) {
+                    int rowDistance = Math.abs(piece.getRow() - row);
+                    int columnDistance = Math.abs(piece.getColumn() - column);
+                    if(Math.max(rowDistance, columnDistance) < 2) {
                         return piece;
                     }
                 }
@@ -197,4 +198,4 @@ public void reset() {
             ((GenericPiece) piece).reset();
         }
     }
-}
\ No newline at end of file
+}