diff --git a/noxfile.py b/noxfile.py
index e3f4d5c..0ab6290 100644
--- a/noxfile.py
+++ b/noxfile.py
@@ -103,7 +103,7 @@ def default(session, tests_path):
     session.run(
         "py.test",
         "--quiet",
-        f"--junitxml=unit_{session.python}_sponge_log.xml",
+        f"--junitxml={os.path.split(tests_path)[-1]}_{session.python}_sponge_log.xml",
         "--cov=db_dtypes",
         "--cov=tests/unit",
         "--cov-append",
@@ -179,7 +179,7 @@ def prerelease(session, tests_path):
     session.run(
         "py.test",
         "--quiet",
-        f"--junitxml=prerelease_unit_{session.python}_sponge_log.xml",
+        f"--junitxml={os.path.split(tests_path)[-1]}_prerelease_{session.python}_sponge_log.xml",
         "--cov=db_dtypes",
         "--cov=tests/unit",
         "--cov-append",
diff --git a/owlbot.py b/owlbot.py
index ec5a5bf..383ae37 100644
--- a/owlbot.py
+++ b/owlbot.py
@@ -81,6 +81,11 @@
     ["noxfile.py"], r"def default\(session\):", "def default(session, tests_path):"
 )
 s.replace(["noxfile.py"], r'os.path.join\("tests", "unit"\),', "tests_path,")
+s.replace(
+    ["noxfile.py"],
+    r'f"--junitxml=unit_{session.python}_sponge_log.xml",',
+    r'f"--junitxml={os.path.split(tests_path)[-1]}_{session.python}_sponge_log.xml",',
+)
 s.replace(
     ["noxfile.py"],
     r'''
@@ -154,7 +159,7 @@ def prerelease(session, tests_path):
     session.run(
         "py.test",
         "--quiet",
-        f"--junitxml=prerelease_unit_{session.python}_sponge_log.xml",
+        f"--junitxml={os.path.split(tests_path)[-1]}_prerelease_{session.python}_sponge_log.xml",
         "--cov=db_dtypes",
         "--cov=tests/unit",
         "--cov-append",