diff --git a/doc/fixes37.0 b/doc/fixes37.0
index c8260d6b8..b043ae707 100644
--- a/doc/fixes37.0
+++ b/doc/fixes37.0
@@ -164,6 +164,8 @@ some monster code was checking whether pets or engulfers were eating green
 	slime by checking for green slime corpse instead of glob
 change light radius of stack of candles to square root
 could get redundate "mon hits other-mon" messages when mon wields an artifact
+failed untrap while mounted that moved hero onto the trap would leave steed
+	with stale coordinates, triggering warnings if 'sanity_check' is On
 
 
 Fixes to 3.7.0-x Problems that Were Exposed Via git Repository
diff --git a/src/hack.c b/src/hack.c
index fa221844f..b5a92d4b2 100644
--- a/src/hack.c
+++ b/src/hack.c
@@ -1416,8 +1416,8 @@ domove_core()
     }
     if (u.uswallow) {
         u.dx = u.dy = 0;
-        u.ux = x = u.ustuck->mx;
-        u.uy = y = u.ustuck->my;
+        x = u.ustuck->mx, y = u.ustuck->my;
+        u_on_newpos(x, y); /* set u.ux,uy and handle CLIPPING */
         mtmp = u.ustuck;
     } else {
         if (Is_airlevel(&u.uz) && rn2(4) && !Levitation && !Flying) {
@@ -1777,15 +1777,15 @@ domove_core()
     if (!in_out_region(x, y))
         return;
 
-    /* now move the hero */
     mtmp = m_at(x, y);
+    /* tentaively move the hero plus steed; leave CLIPPING til later */
     u.ux += u.dx;
     u.uy += u.dy;
-    /* Move your steed, too */
     if (u.usteed) {
         u.usteed->mx = u.ux;
         u.usteed->my = u.uy;
-        exercise_steed();
+        /* [if move attempt ends up being blocked, should training count?] */
+        exercise_steed(); /* train riding skill */
     }
 
     /*
@@ -1911,10 +1911,15 @@ domove_core()
 
         if (didnt_move) {
             u.ux = u.ux0, u.uy = u.uy0; /* didn't move after all */
+            /* could skip this bit since we're about to call u_on_newpos() */
             if (u.usteed)
                 u.usteed->mx = u.ux, u.usteed->my = u.uy;
         }
     }
+    /* tentative move above didn't handle CLIPPING, in case there was a
+       monster in the way and the move attempt ended up being blocked;
+       do a full re-position now, possibly back to where hero started */
+    u_on_newpos(u.ux, u.uy);
 
     reset_occupations();
     if (g.context.run) {
diff --git a/src/trap.c b/src/trap.c
index c810af652..b94f2c7cd 100644
--- a/src/trap.c
+++ b/src/trap.c
@@ -4035,7 +4035,8 @@ struct trap *ttmp;
     if (!Punished
         || drag_ball(x, y, &bc, &bx, &by, &cx, &cy, &unused, TRUE)) {
         u.ux0 = u.ux, u.uy0 = u.uy;
-        u.ux = x, u.uy = y;
+        /* set u.ux,u.uy and u.usteed->mx,my plus handle CLIPPING */
+        u_on_newpos(x, y);
         u.umoved = TRUE;
         newsym(u.ux0, u.uy0);
         vision_recalc(1);