diff --git a/AUTHORS.rst b/AUTHORS.rst
index bc59f500c..9879a302b 100644
--- a/AUTHORS.rst
+++ b/AUTHORS.rst
@@ -84,6 +84,7 @@ The following wonderful people contributed directly or indirectly to this projec
 - `Oleg Sushchenko <https://github.com/feuillemorte>`_
 - `Or Bin <https://github.com/OrBin>`_
 - `overquota <https://github.com/overquota>`_
+- `Paradox <https://github.com/paradox70>`_
 - `Patrick Hofmann <https://github.com/PH89>`_
 - `Paul Larsen <https://github.com/PaulSonOfLars>`_
 - `Pieter Schutz <https://github.com/eldinnie>`_
diff --git a/telegram/utils/request.py b/telegram/utils/request.py
index f2c35bfdf..7362be590 100644
--- a/telegram/utils/request.py
+++ b/telegram/utils/request.py
@@ -58,7 +58,7 @@ except ImportError:  # pragma: no cover
         raise
 
 # pylint: disable=C0412
-from telegram import InputFile, InputMedia, TelegramError
+from telegram import InputFile, TelegramError
 from telegram.error import (
     BadRequest,
     ChatMigrated,
@@ -325,13 +325,9 @@ class Request:
                 # Urllib3 doesn't like floats it seems
                 data[key] = str(val)
             elif key == 'media':
-                # One media or multiple
-                if isinstance(val, InputMedia):
-                    # Attach and set val to attached name
-                    data[key] = val.to_json()
-                    if isinstance(val.media, InputFile):  # type: ignore
-                        data[val.media.attach] = val.media.field_tuple  # type: ignore
-                else:
+                files = True
+                # List of media
+                if isinstance(val, list):
                     # Attach and set val to attached name for all
                     media = []
                     for med in val:
@@ -343,7 +339,16 @@ class Request:
                             if "thumb" in media_dict:
                                 data[med.thumb.attach] = med.thumb.field_tuple
                     data[key] = json.dumps(media)
-                files = True
+                # Single media
+                else:
+                    # Attach and set val to attached name
+                    media_dict = val.to_dict()
+                    if isinstance(val.media, InputFile):
+                        data[val.media.attach] = val.media.field_tuple
+                        # if the file has a thumb, we also need to attach it to the data
+                        if "thumb" in media_dict:
+                            data[val.thumb.attach] = val.thumb.field_tuple
+                    data[key] = json.dumps(media_dict)
             elif isinstance(val, list):
                 # In case we're sending files, we need to json-dump lists manually
                 # As we can't know if that's the case, we just json-dump here
diff --git a/tests/test_inputmedia.py b/tests/test_inputmedia.py
index 5f0d10b65..a23d96987 100644
--- a/tests/test_inputmedia.py
+++ b/tests/test_inputmedia.py
@@ -591,6 +591,21 @@ class TestSendMediaGroup:
         )
         assert isinstance(new_message, Message)
 
+    def test_edit_message_media_with_thumb(
+        self, bot, chat_id, video_file, photo_file, monkeypatch  # noqa: F811
+    ):
+        def test(*args, **kwargs):
+            data = kwargs['fields']
+            video_check = data[input_video.media.attach] == input_video.media.field_tuple
+            thumb_check = data[input_video.thumb.attach] == input_video.thumb.field_tuple
+            result = video_check and thumb_check
+            raise Exception(f"Test was {'successful' if result else 'failing'}")
+
+        monkeypatch.setattr('telegram.utils.request.Request._request_wrapper', test)
+        input_video = InputMediaVideo(video_file, thumb=photo_file)
+        with pytest.raises(Exception, match='Test was successful'):
+            bot.edit_message_media(chat_id=chat_id, message_id=123, media=input_video)
+
     @flaky(3, 1)
     @pytest.mark.parametrize(
         'default_bot', [{'parse_mode': ParseMode.HTML}], indirect=True, ids=['HTML-Bot']