diff --git a/tests/regression_tests/model_xml/test.py b/tests/regression_tests/model_xml/test.py
index 9da5438db6..8aa9e5c2e2 100644
--- a/tests/regression_tests/model_xml/test.py
+++ b/tests/regression_tests/model_xml/test.py
@@ -1,6 +1,8 @@
 from difflib import unified_diff
+import glob
 import filecmp
 import os
+from pathlib import Path
 
 import openmc
 import pytest
@@ -83,13 +85,17 @@ def test_input_arg(run_in_tmpdir):
     pincell.export_to_xml(separate_xmls=True)
     openmc.run()
 
+    # make sure the executable isn't falling back on the separate XMLs
+    [os.remove(f) for f in glob.glob('*.xml')]
     # now export to a single XML file with a custom name
-    pincell.export_to_xml(filename='pincell.xml', separate_xmls=False)
+    pincell.export_to_xml(path='pincell.xml', separate_xmls=False)
+    assert Path('pincell.xml').exists()
 
     # run by specifying that single file
-    openmc.run(input_file='pincell.xml')
+    openmc.run(path_input='pincell.xml')
 
     # now ensure we get an error for an incorrect filename,
     # even in the presence of other, valid XML files
+    pincell.export_to_xml(separate_xmls=True)
     with pytest.raises(RuntimeError, match='ex-em-ell.xml'):
-        openmc.run(input_file='ex-em-ell.xml')
\ No newline at end of file
+        openmc.run(path_input='ex-em-ell.xml')
\ No newline at end of file
diff --git a/tests/unit_tests/test_model.py b/tests/unit_tests/test_model.py
index 5d4765d657..11a88d76ce 100644
--- a/tests/unit_tests/test_model.py
+++ b/tests/unit_tests/test_model.py
@@ -543,7 +543,7 @@ def test_model_xml(run_in_tmpdir):
 
     # now write and read a model.xml file
     pwr_model.export_to_xml(separate_xmls=False)
-    new_model = openmc.Model.from_xml(separate_xmls=False)
+    new_model = openmc.Model.from_model_xml()
 
     # make sure we can also export this again to separate
     # XML files
@@ -553,17 +553,17 @@ def test_model_exec(run_in_tmpdir):
 
     pincell_model = openmc.examples.pwr_pin_cell()
 
-    pincell_model.export_to_xml(filename='pwr_pincell.xml', separate_xmls=False)
+    pincell_model.export_to_xml(path='pwr_pincell.xml', separate_xmls=False)
 
-    openmc.run(input_file='pwr_pincell.xml')
+    openmc.run(path_input='pwr_pincell.xml')
 
     with pytest.raises(RuntimeError, match='ex-em-ell.xml'):
-        openmc.run(input_file='ex-em-ell.xml')
+        openmc.run(path_input='ex-em-ell.xml')
 
     # test that a file in a different directory can be used
     os.mkdir('inputs')
-    pincell_model.export_to_xml(directory='./inputs', filename='pincell.xml', separate_xmls=False)
-    openmc.run(input_file='./inputs/pincell.xml')
+    pincell_model.export_to_xml(path='./inputs/pincell.xml', separate_xmls=False)
+    openmc.run(path_input='./inputs/pincell.xml')
 
     with pytest.raises(RuntimeError, match='input_dir'):
-        openmc.run(input_file='input_dir/pincell.xml')
\ No newline at end of file
+        openmc.run(path_input='input_dir/pincell.xml')
\ No newline at end of file