diff --git a/builtin/blame.c b/builtin/blame.c
index 6fd1a63fc7..01ea770787 100644
--- a/builtin/blame.c
+++ b/builtin/blame.c
@@ -1366,8 +1366,15 @@ static void pass_whole_blame(struct scoreboard *sb,
  */
 static struct commit_list *first_scapegoat(struct rev_info *revs, struct commit *commit)
 {
-	if (!reverse)
+	if (!reverse) {
+		if (revs->first_parent_only &&
+		    commit->parents &&
+		    commit->parents->next) {
+			free_commit_list(commit->parents->next);
+			commit->parents->next = NULL;
+		}
 		return commit->parents;
+	}
 	return lookup_decoration(&revs->children, &commit->object);
 }
 
@@ -2679,6 +2686,8 @@ int cmd_blame(int argc, const char **argv, const char *prefix)
 	}
 	else if (contents_from)
 		die("--contents and --children do not blend well.");
+	else if (revs.first_parent_only)
+		die("combining --first-parent and --reverse is not supported");
 	else {
 		final_commit_name = prepare_initial(&sb);
 		sb.commits.compare = compare_commits_by_reverse_commit_date;
diff --git a/t/annotate-tests.sh b/t/annotate-tests.sh
index f5c01758ca..b1673b3e8f 100644
--- a/t/annotate-tests.sh
+++ b/t/annotate-tests.sh
@@ -111,6 +111,10 @@ test_expect_success 'blame 2 authors + 2 merged-in authors' '
 	check_count A 2 B 1 B1 2 B2 1
 '
 
+test_expect_success 'blame --first-parent blames merge for branch1' '
+	check_count --first-parent A 2 B 1 "A U Thor" 2 B2 1
+'
+
 test_expect_success 'blame ancestor' '
 	check_count -h master A 2 B 2
 '