diff --git a/builtin/fetch.c b/builtin/fetch.c
index 3aedfd1bb6..0a7a1a3476 100644
--- a/builtin/fetch.c
+++ b/builtin/fetch.c
@@ -448,9 +448,8 @@ static void filter_prefetch_refspec(struct refspec *rs)
 			continue;
 		if (!rs->items[i].dst ||
 		    (rs->items[i].src &&
-		     !strncmp(rs->items[i].src,
-			      ref_namespace[NAMESPACE_TAGS].ref,
-			      strlen(ref_namespace[NAMESPACE_TAGS].ref)))) {
+		     starts_with(rs->items[i].src,
+				 ref_namespace[NAMESPACE_TAGS].ref))) {
 			int j;
 
 			free(rs->items[i].src);