diff --git a/Tests/test_file_blp.py b/Tests/test_file_blp.py
index f64a9d420..5f6b263a1 100644
--- a/Tests/test_file_blp.py
+++ b/Tests/test_file_blp.py
@@ -60,7 +60,7 @@ def test_save(tmp_path: Path) -> None:
             assert_image_similar_tofile(im, f, 8)
 
     im = hopper()
-    with pytest.raises(ValueError):
+    with pytest.raises(ValueError, match="Unsupported BLP image mode"):
         im.save(f)