diff --git a/builtin/fetch.c b/builtin/fetch.c
index e0140327aa..91f9b7d9c8 100644
--- a/builtin/fetch.c
+++ b/builtin/fetch.c
@@ -763,9 +763,6 @@ static int update_local_ref(struct ref *ref,
 			what = _("[new ref]");
 		}
 
-		if ((recurse_submodules != RECURSE_SUBMODULES_OFF) &&
-		    (recurse_submodules != RECURSE_SUBMODULES_ON))
-			check_for_new_submodule_commits(&ref->new_oid);
 		r = s_update_ref(msg, ref, 0);
 		format_display(display, r ? '!' : '*', what,
 			       r ? _("unable to update local ref") : NULL,
@@ -779,9 +776,6 @@ static int update_local_ref(struct ref *ref,
 		strbuf_add_unique_abbrev(&quickref, &current->object.oid, DEFAULT_ABBREV);
 		strbuf_addstr(&quickref, "..");
 		strbuf_add_unique_abbrev(&quickref, &ref->new_oid, DEFAULT_ABBREV);
-		if ((recurse_submodules != RECURSE_SUBMODULES_OFF) &&
-		    (recurse_submodules != RECURSE_SUBMODULES_ON))
-			check_for_new_submodule_commits(&ref->new_oid);
 		r = s_update_ref("fast-forward", ref, 1);
 		format_display(display, r ? '!' : ' ', quickref.buf,
 			       r ? _("unable to update local ref") : NULL,
@@ -794,9 +788,6 @@ static int update_local_ref(struct ref *ref,
 		strbuf_add_unique_abbrev(&quickref, &current->object.oid, DEFAULT_ABBREV);
 		strbuf_addstr(&quickref, "...");
 		strbuf_add_unique_abbrev(&quickref, &ref->new_oid, DEFAULT_ABBREV);
-		if ((recurse_submodules != RECURSE_SUBMODULES_OFF) &&
-		    (recurse_submodules != RECURSE_SUBMODULES_ON))
-			check_for_new_submodule_commits(&ref->new_oid);
 		r = s_update_ref("forced-update", ref, 1);
 		format_display(display, r ? '!' : '+', quickref.buf,
 			       r ? _("unable to update local ref") : _("forced update"),
@@ -892,6 +883,8 @@ static int store_updated_refs(const char *raw_url, const char *remote_name,
 				ref->force = rm->peer_ref->force;
 			}
 
+			if (recurse_submodules != RECURSE_SUBMODULES_OFF)
+				check_for_new_submodule_commits(&rm->old_oid);
 
 			if (!strcmp(rm->name, "HEAD")) {
 				kind = "";
diff --git a/submodule.c b/submodule.c
index d1b6646f42..b88343d977 100644
--- a/submodule.c
+++ b/submodule.c
@@ -1231,8 +1231,14 @@ struct submodule_parallel_fetch {
 	int result;
 
 	struct string_list changed_submodule_names;
+
+	/* Pending fetches by OIDs */
+	struct fetch_task **oid_fetch_tasks;
+	int oid_fetch_tasks_nr, oid_fetch_tasks_alloc;
 };
-#define SPF_INIT {0, ARGV_ARRAY_INIT, NULL, NULL, 0, 0, 0, 0, STRING_LIST_INIT_DUP }
+#define SPF_INIT {0, ARGV_ARRAY_INIT, NULL, NULL, 0, 0, 0, 0, \
+		  STRING_LIST_INIT_DUP, \
+		  NULL, 0, 0}
 
 static int get_fetch_recurse_config(const struct submodule *submodule,
 				    struct submodule_parallel_fetch *spf)
@@ -1259,6 +1265,76 @@ static int get_fetch_recurse_config(const struct submodule *submodule,
 	return spf->default_option;
 }
 
+/*
+ * Fetch in progress (if callback data) or
+ * pending (if in oid_fetch_tasks in struct submodule_parallel_fetch)
+ */
+struct fetch_task {
+	struct repository *repo;
+	const struct submodule *sub;
+	unsigned free_sub : 1; /* Do we need to free the submodule? */
+
+	struct oid_array *commits; /* Ensure these commits are fetched */
+};
+
+/**
+ * When a submodule is not defined in .gitmodules, we cannot access it
+ * via the regular submodule-config. Create a fake submodule, which we can
+ * work on.
+ */
+static const struct submodule *get_non_gitmodules_submodule(const char *path)
+{
+	struct submodule *ret = NULL;
+	const char *name = default_name_or_path(path);
+
+	if (!name)
+		return NULL;
+
+	ret = xmalloc(sizeof(*ret));
+	memset(ret, 0, sizeof(*ret));
+	ret->path = name;
+	ret->name = name;
+
+	return (const struct submodule *) ret;
+}
+
+static struct fetch_task *fetch_task_create(struct repository *r,
+					    const char *path)
+{
+	struct fetch_task *task = xmalloc(sizeof(*task));
+	memset(task, 0, sizeof(*task));
+
+	task->sub = submodule_from_path(r, &null_oid, path);
+	if (!task->sub) {
+		/*
+		 * No entry in .gitmodules? Technically not a submodule,
+		 * but historically we supported repositories that happen to be
+		 * in-place where a gitlink is. Keep supporting them.
+		 */
+		task->sub = get_non_gitmodules_submodule(path);
+		if (!task->sub) {
+			free(task);
+			return NULL;
+		}
+
+		task->free_sub = 1;
+	}
+
+	return task;
+}
+
+static void fetch_task_release(struct fetch_task *p)
+{
+	if (p->free_sub)
+		free((void*)p->sub);
+	p->free_sub = 0;
+	p->sub = NULL;
+
+	if (p->repo)
+		repo_clear(p->repo);
+	FREE_AND_NULL(p->repo);
+}
+
 static struct repository *get_submodule_repo_for(struct repository *r,
 						 const struct submodule *sub)
 {
@@ -1286,39 +1362,29 @@ static struct repository *get_submodule_repo_for(struct repository *r,
 static int get_next_submodule(struct child_process *cp,
 			      struct strbuf *err, void *data, void **task_cb)
 {
-	int ret = 0;
 	struct submodule_parallel_fetch *spf = data;
 
 	for (; spf->count < spf->r->index->cache_nr; spf->count++) {
-		struct strbuf submodule_prefix = STRBUF_INIT;
 		const struct cache_entry *ce = spf->r->index->cache[spf->count];
 		const char *default_argv;
-		const struct submodule *submodule;
-		struct repository *repo;
-		struct submodule default_submodule = SUBMODULE_INIT;
+		struct fetch_task *task;
 
 		if (!S_ISGITLINK(ce->ce_mode))
 			continue;
 
-		submodule = submodule_from_path(spf->r, &null_oid, ce->name);
-		if (!submodule) {
-			const char *name = default_name_or_path(ce->name);
-			if (name) {
-				default_submodule.path = name;
-				default_submodule.name = name;
-				submodule = &default_submodule;
-			}
-		}
+		task = fetch_task_create(spf->r, ce->name);
+		if (!task)
+			continue;
 
-		switch (get_fetch_recurse_config(submodule, spf))
+		switch (get_fetch_recurse_config(task->sub, spf))
 		{
 		default:
 		case RECURSE_SUBMODULES_DEFAULT:
 		case RECURSE_SUBMODULES_ON_DEMAND:
-			if (!submodule ||
+			if (!task->sub ||
 			    !string_list_lookup(
 					&spf->changed_submodule_names,
-					submodule->name))
+					task->sub->name))
 				continue;
 			default_argv = "on-demand";
 			break;
@@ -1329,11 +1395,11 @@ static int get_next_submodule(struct child_process *cp,
 			continue;
 		}
 
-		strbuf_addf(&submodule_prefix, "%s%s/", spf->prefix, ce->name);
-		repo = get_submodule_repo_for(spf->r, submodule);
-		if (repo) {
+		task->repo = get_submodule_repo_for(spf->r, task->sub);
+		if (task->repo) {
+			struct strbuf submodule_prefix = STRBUF_INIT;
 			child_process_init(cp);
-			cp->dir = xstrdup(repo->gitdir);
+			cp->dir = task->repo->gitdir;
 			prepare_submodule_repo_env_in_gitdir(&cp->env_array);
 			cp->git_cmd = 1;
 			if (!spf->quiet)
@@ -1343,12 +1409,22 @@ static int get_next_submodule(struct child_process *cp,
 			argv_array_pushv(&cp->args, spf->args.argv);
 			argv_array_push(&cp->args, default_argv);
 			argv_array_push(&cp->args, "--submodule-prefix");
+
+			strbuf_addf(&submodule_prefix, "%s%s/",
+						       spf->prefix,
+						       task->sub->path);
 			argv_array_push(&cp->args, submodule_prefix.buf);
 
-			repo_clear(repo);
-			free(repo);
-			ret = 1;
+			spf->count++;
+			*task_cb = task;
+
+			strbuf_release(&submodule_prefix);
+			return 1;
 		} else {
+
+			fetch_task_release(task);
+			free(task);
+
 			/*
 			 * An empty directory is normal,
 			 * the submodule is not initialized
@@ -1361,12 +1437,38 @@ static int get_next_submodule(struct child_process *cp,
 					    ce->name);
 			}
 		}
+	}
+
+	if (spf->oid_fetch_tasks_nr) {
+		struct fetch_task *task =
+			spf->oid_fetch_tasks[spf->oid_fetch_tasks_nr - 1];
+		struct strbuf submodule_prefix = STRBUF_INIT;
+		spf->oid_fetch_tasks_nr--;
+
+		strbuf_addf(&submodule_prefix, "%s%s/",
+			    spf->prefix, task->sub->path);
+
+		child_process_init(cp);
+		prepare_submodule_repo_env_in_gitdir(&cp->env_array);
+		cp->git_cmd = 1;
+		cp->dir = task->repo->gitdir;
+
+		argv_array_init(&cp->args);
+		argv_array_pushv(&cp->args, spf->args.argv);
+		argv_array_push(&cp->args, "on-demand");
+		argv_array_push(&cp->args, "--submodule-prefix");
+		argv_array_push(&cp->args, submodule_prefix.buf);
+
+		/* NEEDSWORK: have get_default_remote from submodule--helper */
+		argv_array_push(&cp->args, "origin");
+		oid_array_for_each_unique(task->commits,
+					  append_oid_to_argv, &cp->args);
+
+		*task_cb = task;
 		strbuf_release(&submodule_prefix);
-		if (ret) {
-			spf->count++;
-			return 1;
-		}
+		return 1;
 	}
+
 	return 0;
 }
 
@@ -1374,20 +1476,66 @@ static int fetch_start_failure(struct strbuf *err,
 			       void *cb, void *task_cb)
 {
 	struct submodule_parallel_fetch *spf = cb;
+	struct fetch_task *task = task_cb;
 
 	spf->result = 1;
 
+	fetch_task_release(task);
 	return 0;
 }
 
+static int commit_missing_in_sub(const struct object_id *oid, void *data)
+{
+	struct repository *subrepo = data;
+
+	enum object_type type = oid_object_info(subrepo, oid, NULL);
+
+	return type != OBJ_COMMIT;
+}
+
 static int fetch_finish(int retvalue, struct strbuf *err,
 			void *cb, void *task_cb)
 {
 	struct submodule_parallel_fetch *spf = cb;
+	struct fetch_task *task = task_cb;
+
+	struct string_list_item *it;
+	struct oid_array *commits;
 
 	if (retvalue)
 		spf->result = 1;
 
+	if (!task || !task->sub)
+		BUG("callback cookie bogus");
+
+	/* Is this the second time we process this submodule? */
+	if (task->commits)
+		goto out;
+
+	it = string_list_lookup(&spf->changed_submodule_names, task->sub->name);
+	if (!it)
+		/* Could be an unchanged submodule, not contained in the list */
+		goto out;
+
+	commits = it->util;
+	oid_array_filter(commits,
+			 commit_missing_in_sub,
+			 task->repo);
+
+	/* Are there commits we want, but do not exist? */
+	if (commits->nr) {
+		task->commits = commits;
+		ALLOC_GROW(spf->oid_fetch_tasks,
+			   spf->oid_fetch_tasks_nr + 1,
+			   spf->oid_fetch_tasks_alloc);
+		spf->oid_fetch_tasks[spf->oid_fetch_tasks_nr] = task;
+		spf->oid_fetch_tasks_nr++;
+		return 0;
+	}
+
+out:
+	fetch_task_release(task);
+
 	return 0;
 }
 
diff --git a/t/t5526-fetch-submodules.sh b/t/t5526-fetch-submodules.sh
index 6c2f9b2ba2..9f8c744eb5 100755
--- a/t/t5526-fetch-submodules.sh
+++ b/t/t5526-fetch-submodules.sh
@@ -600,4 +600,121 @@ test_expect_success "fetch new commits when submodule got renamed" '
 	test_cmp expect actual
 '
 
+test_expect_success "fetch new submodule commits on-demand outside standard refspec" '
+	# add a second submodule and ensure it is around in downstream first
+	git clone submodule sub1 &&
+	git submodule add ./sub1 &&
+	git commit -m "adding a second submodule" &&
+	git -C downstream pull &&
+	git -C downstream submodule update --init --recursive &&
+
+	git checkout --detach &&
+
+	C=$(git -C submodule commit-tree -m "new change outside refs/heads" HEAD^{tree}) &&
+	git -C submodule update-ref refs/changes/1 $C &&
+	git update-index --cacheinfo 160000 $C submodule &&
+	test_tick &&
+
+	D=$(git -C sub1 commit-tree -m "new change outside refs/heads" HEAD^{tree}) &&
+	git -C sub1 update-ref refs/changes/2 $D &&
+	git update-index --cacheinfo 160000 $D sub1 &&
+
+	git commit -m "updated submodules outside of refs/heads" &&
+	E=$(git rev-parse HEAD) &&
+	git update-ref refs/changes/3 $E &&
+	(
+		cd downstream &&
+		git fetch --recurse-submodules origin refs/changes/3:refs/heads/my_branch &&
+		git -C submodule cat-file -t $C &&
+		git -C sub1 cat-file -t $D &&
+		git checkout --recurse-submodules FETCH_HEAD
+	)
+'
+
+test_expect_success 'fetch new submodule commit on-demand in FETCH_HEAD' '
+	# depends on the previous test for setup
+
+	C=$(git -C submodule commit-tree -m "another change outside refs/heads" HEAD^{tree}) &&
+	git -C submodule update-ref refs/changes/4 $C &&
+	git update-index --cacheinfo 160000 $C submodule &&
+	test_tick &&
+
+	D=$(git -C sub1 commit-tree -m "another change outside refs/heads" HEAD^{tree}) &&
+	git -C sub1 update-ref refs/changes/5 $D &&
+	git update-index --cacheinfo 160000 $D sub1 &&
+
+	git commit -m "updated submodules outside of refs/heads" &&
+	E=$(git rev-parse HEAD) &&
+	git update-ref refs/changes/6 $E &&
+	(
+		cd downstream &&
+		git fetch --recurse-submodules origin refs/changes/6 &&
+		git -C submodule cat-file -t $C &&
+		git -C sub1 cat-file -t $D &&
+		git checkout --recurse-submodules FETCH_HEAD
+	)
+'
+
+test_expect_success 'fetch new submodule commits on-demand without .gitmodules entry' '
+	# depends on the previous test for setup
+
+	git config -f .gitmodules --remove-section submodule.sub1 &&
+	git add .gitmodules &&
+	git commit -m "delete gitmodules file" &&
+	git checkout -B master &&
+	git -C downstream fetch &&
+	git -C downstream checkout origin/master &&
+
+	C=$(git -C submodule commit-tree -m "yet another change outside refs/heads" HEAD^{tree}) &&
+	git -C submodule update-ref refs/changes/7 $C &&
+	git update-index --cacheinfo 160000 $C submodule &&
+	test_tick &&
+
+	D=$(git -C sub1 commit-tree -m "yet another change outside refs/heads" HEAD^{tree}) &&
+	git -C sub1 update-ref refs/changes/8 $D &&
+	git update-index --cacheinfo 160000 $D sub1 &&
+
+	git commit -m "updated submodules outside of refs/heads" &&
+	E=$(git rev-parse HEAD) &&
+	git update-ref refs/changes/9 $E &&
+	(
+		cd downstream &&
+		git fetch --recurse-submodules origin refs/changes/9 &&
+		git -C submodule cat-file -t $C &&
+		git -C sub1 cat-file -t $D &&
+		git checkout --recurse-submodules FETCH_HEAD
+	)
+'
+
+test_expect_success 'fetch new submodule commit intermittently referenced by superproject' '
+	# depends on the previous test for setup
+
+	D=$(git -C sub1 commit-tree -m "change 10 outside refs/heads" HEAD^{tree}) &&
+	E=$(git -C sub1 commit-tree -m "change 11 outside refs/heads" HEAD^{tree}) &&
+	F=$(git -C sub1 commit-tree -m "change 12 outside refs/heads" HEAD^{tree}) &&
+
+	git -C sub1 update-ref refs/changes/10 $D &&
+	git update-index --cacheinfo 160000 $D sub1 &&
+	git commit -m "updated submodules outside of refs/heads" &&
+
+	git -C sub1 update-ref refs/changes/11 $E &&
+	git update-index --cacheinfo 160000 $E sub1 &&
+	git commit -m "updated submodules outside of refs/heads" &&
+
+	git -C sub1 update-ref refs/changes/12 $F &&
+	git update-index --cacheinfo 160000 $F sub1 &&
+	git commit -m "updated submodules outside of refs/heads" &&
+
+	G=$(git rev-parse HEAD) &&
+	git update-ref refs/changes/13 $G &&
+	(
+		cd downstream &&
+		git fetch --recurse-submodules origin refs/changes/13 &&
+
+		git -C sub1 cat-file -t $D &&
+		git -C sub1 cat-file -t $E &&
+		git -C sub1 cat-file -t $F
+	)
+'
+
 test_done
