diff --git a/src/endgame.cpp b/src/endgame.cpp
index a95ff3731..0639d7a10 100644
--- a/src/endgame.cpp
+++ b/src/endgame.cpp
@@ -172,8 +172,8 @@ Value Endgame<KBNK>::operator()(const Position& pos) const {
 template<>
 Value Endgame<KPK>::operator()(const Position& pos) const {
 
-  assert(verify_material(pos, strongSide, VALUE_ZERO, 1));
-  assert(verify_material(pos, weakSide, VALUE_ZERO, 0));
+assert(verify_material(pos, strongSide, VALUE_VIRTUAL_MATE, 1));
+assert(verify_material(pos, weakSide, VALUE_VIRTUAL_LOSS, 0));
 
   // Assume strongSide is white and the pawn is on files A-D
   Square strongKing = normalize(pos, strongSide, pos.square<KING>(strongSide));
diff --git a/src/types.h b/src/types.h
index 0c398412a..877e4435b 100644
--- a/src/types.h
+++ b/src/types.h
@@ -336,6 +336,7 @@ enum Value : int {
   VALUE_MATE      = 32000,
   XBOARD_VALUE_MATE = 200000,
   VALUE_VIRTUAL_MATE = 3000,
+  VALUE_VIRTUAL_LOSS = -3000,
   VALUE_VIRTUAL_MATE_IN_MAX_PLY = VALUE_VIRTUAL_MATE - MAX_PLY,
   VALUE_INFINITE  = 32001,
   VALUE_NONE      = 32002,
@@ -345,11 +346,11 @@ enum Value : int {
   VALUE_MATE_IN_MAX_PLY  =  VALUE_MATE - MAX_PLY,
   VALUE_MATED_IN_MAX_PLY = -VALUE_MATE_IN_MAX_PLY,
 
-  PawnValueMg   = 126,   PawnValueEg   = 208,
-  KnightValueMg = 781,   KnightValueEg = 854,
-  BishopValueMg = 825,   BishopValueEg = 915,
-  RookValueMg   = 1276,  RookValueEg   = 1380,
-  QueenValueMg  = 2538,  QueenValueEg  = 2682,
+  PawnValueMg   = 116,   PawnValueEg   = 186,
+  KnightValueMg = 261,   KnightValueEg = 444,
+  BishopValueMg = 100,   BishopValueEg = 100,
+  RookValueMg   = 204,  RookValueEg   = 244,
+  QueenValueMg  = 427,  QueenValueEg  = 798,
   FersValueMg              = 420,   FersValueEg              = 450,
   AlfilValueMg             = 350,   AlfilValueEg             = 330,
   FersAlfilValueMg         = 700,   FersAlfilValueEg         = 650,