diff --git a/src/fix_external.cpp b/src/fix_external.cpp
index c0cfbe1c70..3bbc92fda6 100644
--- a/src/fix_external.cpp
+++ b/src/fix_external.cpp
@@ -47,6 +47,7 @@ int FixExternal::setmask()
 {
   int mask = 0;
   mask |= POST_FORCE;
+  mask |= MIN_POST_FORCE;
   return mask;
 }
 
@@ -66,6 +67,13 @@ void FixExternal::setup(int vflag)
 
 /* ---------------------------------------------------------------------- */
 
+void FixExternal::min_setup(int vflag)
+{
+  post_force(vflag);
+}
+
+/* ---------------------------------------------------------------------- */
+
 void FixExternal::post_force(int vflag)
 {
   if (atom->nlocal > nmax) {
@@ -94,6 +102,13 @@ void FixExternal::post_force(int vflag)
     }
 }
 
+/* ---------------------------------------------------------------------- */
+
+void FixExternal::min_post_force(int vflag)
+{
+  post_force(vflag);
+}
+
 /* ----------------------------------------------------------------------
    external caller sets a callback function to invoke in post_force()
 ------------------------------------------------------------------------- */
diff --git a/src/fix_external.h b/src/fix_external.h
index 434c46261a..231a2e56a7 100644
--- a/src/fix_external.h
+++ b/src/fix_external.h
@@ -31,7 +31,9 @@ class FixExternal : public Fix {
   int setmask();
   void init();
   void setup(int);
+  void min_setup(int);
   void post_force(int);
+  void min_post_force(int);
 
   typedef void (*FnPtr)(void *, int, int, int *, double **, double **);
   void set_callback(FnPtr, void *);