diff --git a/client/mysql.cc b/client/mysql.cc
index f581bfcafae..c043d054ea5 100644
--- a/client/mysql.cc
+++ b/client/mysql.cc
@@ -1094,7 +1094,7 @@ inline bool is_delimiter_command(char *name, ulong len)
     only name(first DELIMITER_NAME_LEN bytes) is checked.
   */
   return (len >= DELIMITER_NAME_LEN &&
-          !my_strnncoll(charset_info, (uchar*) name, DELIMITER_NAME_LEN,
+          !my_strnncoll(&my_charset_latin1, (uchar*) name, DELIMITER_NAME_LEN,
                         (uchar *) DELIMITER_NAME, DELIMITER_NAME_LEN));
 }
 
diff --git a/mysql-test/r/delimiter_command_case_sensitivity.result b/mysql-test/r/delimiter_command_case_sensitivity.result
new file mode 100644
index 00000000000..6ed281c757a
--- /dev/null
+++ b/mysql-test/r/delimiter_command_case_sensitivity.result
@@ -0,0 +1,2 @@
+1
+1
diff --git a/mysql-test/t/delimiter_case_mdev_10728.sql b/mysql-test/t/delimiter_case_mdev_10728.sql
new file mode 100644
index 00000000000..72a1dcd9a9e
--- /dev/null
+++ b/mysql-test/t/delimiter_case_mdev_10728.sql
@@ -0,0 +1,3 @@
+DeLiMiTeR A;
+SELECT 1 A;
+delimiter ;
diff --git a/mysql-test/t/delimiter_command_case_sensitivity.test b/mysql-test/t/delimiter_command_case_sensitivity.test
new file mode 100644
index 00000000000..2b06a35c723
--- /dev/null
+++ b/mysql-test/t/delimiter_command_case_sensitivity.test
@@ -0,0 +1,2 @@
+# MDEV-10728
+--exec $MYSQL --default-character-set=binary < "t/delimiter_case_mdev_10728.sql"