diff --git a/ollama/_types.py b/ollama/_types.py
index 96529d6..1278b54 100644
--- a/ollama/_types.py
+++ b/ollama/_types.py
@@ -98,7 +98,7 @@ def get(self, key: str, default: Any = None) -> Any:
     >>> msg.get('tool_calls')[0]['function']['name']
     'foo'
     """
-    return getattr(self, key) if hasattr(self, key) else default
+    return getattr(self, key) if key in self else default
 
 
 class Options(SubscriptableBaseModel):
diff --git a/tests/test_type_serialization.py b/tests/test_type_serialization.py
index f458cd2..fd41622 100644
--- a/tests/test_type_serialization.py
+++ b/tests/test_type_serialization.py
@@ -4,7 +4,19 @@
 
 import pytest
 
-from ollama._types import CreateRequest, Image
+from ollama._types import CreateRequest, Image, Message
+
+
+def test_subscriptable_model_get_returns_default_for_unset_field():
+  message = Message(role='user')
+
+  assert 'content' not in message
+  assert message.get('content', 'fallback') == 'fallback'
+
+  message.content = None
+
+  assert 'content' in message
+  assert message.get('content', 'fallback') is None
 
 
 def test_image_serialization_bytes():