diff --git a/tests/serializers/test_model.py b/tests/serializers/test_model.py
index 9735cd0d3..9fa44032a 100644
--- a/tests/serializers/test_model.py
+++ b/tests/serializers/test_model.py
@@ -15,7 +15,6 @@
 
 from pydantic_core import (
     PydanticSerializationError,
-    PydanticSerializationUnexpectedValue,
     SchemaSerializer,
     SchemaValidator,
     core_schema,
@@ -1150,8 +1149,6 @@ class BModel(BasicModel): ...
         )
     )
 
-    with pytest.raises(
-        PydanticSerializationUnexpectedValue, match='Expected 2 fields but got 1 for type `.*AModel` with value `.*`.+'
-    ):
+    with pytest.warns(UserWarning, match='Expected 2 fields but got 1 for type `.*AModel` with value `.*`.+'):
         value = BasicModel(root=AModel(type='a'))
         s.to_python(value)
diff --git a/tests/serializers/test_union.py b/tests/serializers/test_union.py
index 342f12cf4..8b6d6f128 100644
--- a/tests/serializers/test_union.py
+++ b/tests/serializers/test_union.py
@@ -1,7 +1,7 @@
 import dataclasses
 import json
-import re
 import uuid
+import warnings
 from decimal import Decimal
 from typing import Any, ClassVar, Union
 
@@ -32,9 +32,17 @@ def test_union_bool_int(input_value, expected_value, bool_case_label, int_case_l
 
 def test_union_error():
     s = SchemaSerializer(core_schema.union_schema([core_schema.bool_schema(), core_schema.int_schema()]))
-    msg = "Expected `Union[bool, int]` but got `str` with value `'a string'` - serialized value may not be as expected"
-    with pytest.warns(UserWarning, match=re.escape(msg)):
-        assert s.to_python('a string') == 'a string'
+
+    messages = [
+        "Expected `bool` but got `str` with value `'a string'` - serialized value may not be as expected",
+        "Expected `int` but got `str` with value `'a string'` - serialized value may not be as expected",
+    ]
+
+    with warnings.catch_warnings(record=True) as w:
+        warnings.simplefilter('always')
+        s.to_python('a string')
+        for m in messages:
+            assert m in str(w[0].message)
 
 
 class ModelA: