diff --git a/src/endgame.cpp b/src/endgame.cpp
index 40f49dce..a8ceb648 100644
--- a/src/endgame.cpp
+++ b/src/endgame.cpp
@@ -589,8 +589,8 @@ ScaleFactor Endgame<KPsK>::operator()(const Position& pos) const {
   Bitboard strongPawns = pos.pieces(strongSide, PAWN);
 
   // If all pawns are ahead of the king on a single rook file, it's a draw.
-  if (!((strongPawns & ~FileABB) || (strongPawns & ~FileHBB)) &&
-      !(strongPawns & ~passed_pawn_span(weakSide, weakKing)))
+  if (   !(strongPawns & ~(FileABB | FileHBB))
+      && !(strongPawns & ~passed_pawn_span(weakSide, weakKing)))
       return SCALE_FACTOR_DRAW;
 
   return SCALE_FACTOR_NONE;