diff --git a/src/position.cpp b/src/position.cpp
index dd6ec05b..480a92ec 100644
--- a/src/position.cpp
+++ b/src/position.cpp
@@ -315,9 +315,10 @@ void Position::print(Move m) const {
 
 /// Position::copy() creates a copy of the input position.
 
-void Position::copy(const Position &pos) {
+void Position::copy(const Position& pos) {
 
   memcpy(this, &pos, sizeof(Position));
+  saveState(); // detach and copy state info
 }
 
 
@@ -1607,15 +1608,16 @@ int Position::see(Square from, Square to) const {
 }
 
 
-/// Position::setStartState() copies the content of the argument
+/// Position::saveState() copies the content of the current state
 /// inside startState and makes st point to it. This is needed
 /// when the st pointee could become stale, as example because
 /// the caller is about to going out of scope.
 
-void Position::setStartState(const StateInfo& s) {
+void Position::saveState() {
 
-  startState = s;
+  startState = *st;
   st = &startState;
+  st->previous = NULL; // as a safe guard
 }
 
 
@@ -1966,7 +1968,7 @@ void Position::init_piece_square_tables() {
 /// the white and black sides reversed. This is only useful for debugging,
 /// especially for finding evaluation symmetry bugs.
 
-void Position::flipped_copy(const Position &pos) {
+void Position::flipped_copy(const Position& pos) {
 
   assert(pos.is_ok());
 
diff --git a/src/position.h b/src/position.h
index aa7c7ab8..9737d761 100644
--- a/src/position.h
+++ b/src/position.h
@@ -138,8 +138,8 @@ public:
   void print(Move m = MOVE_NONE) const;
 
   // Copying
-  void copy(const Position &pos);
-  void flipped_copy(const Position &pos);
+  void copy(const Position& pos);
+  void flipped_copy(const Position& pos);
 
   // The piece on a given square
   Piece piece_on(Square s) const;
@@ -250,7 +250,7 @@ public:
   bool square_is_weak(Square s, Color c) const;
 
   // Doing and undoing moves
-  void setStartState(const StateInfo& st);
+  void saveState();
   void do_move(Move m, StateInfo& st);
   void do_move(Move m, StateInfo& st, Bitboard dcCandidates);
   void undo_move(Move m);
diff --git a/src/uci.cpp b/src/uci.cpp
index a6452005..4a333f70 100644
--- a/src/uci.cpp
+++ b/src/uci.cpp
@@ -210,9 +210,9 @@ namespace {
                 if (RootPosition.rule_50_counter() == 0)
                     RootPosition.reset_game_ply();
             }
-            // Our StateInfo st is about going out of scope,
-            // so save its content before they disappear.
-            RootPosition.setStartState(st);
+            // Our StateInfo st is about going out of scope so copy
+            // its content inside RootPosition before they disappear.
+            RootPosition.saveState();
         }
     }
   }