diff --git a/scripts/create_test b/scripts/create_test
index de6eebcd28e..a5c5130e7e5 100755
--- a/scripts/create_test
+++ b/scripts/create_test
@@ -320,6 +320,9 @@ OR
 
         logger.info("Testnames: %s" % test_names)
     else:
+        if args.machine is None:
+            args.machine = update_acme_tests.infer_machine_name_from_tests(args.testargs)
+
         mach_obj = Machines(machine=args.machine)
         args.compiler = mach_obj.get_default_compiler() if args.compiler is None else args.compiler
 
diff --git a/scripts/lib/update_acme_tests.py b/scripts/lib/update_acme_tests.py
index e9ff9f4e583..67d0604585c 100644
--- a/scripts/lib/update_acme_tests.py
+++ b/scripts/lib/update_acme_tests.py
@@ -1,5 +1,5 @@
 import CIME.utils
-from CIME.utils import expect, convert_to_seconds
+from CIME.utils import expect, convert_to_seconds, parse_test_name
 from CIME.XML.machines import Machines
 
 # Here are the tests belonging to acme suites. Format is
@@ -210,6 +210,36 @@ def get_test_suites():
 ###############################################################################
     return _TEST_SUITES.keys()
 
+###############################################################################
+def infer_machine_name_from_tests(testargs):
+###############################################################################
+    """
+    >>> infer_machine_name_from_tests(["NCK.f19_g16_rx1.A.melvin_gnu"])
+    'melvin'
+    >>> infer_machine_name_from_tests(["NCK.f19_g16_rx1.A"])
+    >>> infer_machine_name_from_tests(["NCK.f19_g16_rx1.A", "NCK.f19_g16_rx1.A.melvin_gnu"])
+    'melvin'
+    >>> infer_machine_name_from_tests(["NCK.f19_g16_rx1.A.melvin_gnu", "NCK.f19_g16_rx1.A.melvin_gnu"])
+    'melvin'
+    """
+    acme_test_suites = get_test_suites()
+
+    machine = None
+    for testarg in testargs:
+        testarg = testarg.strip()
+        if testarg.startswith("^"):
+            testarg = testarg[1:]
+
+        if testarg not in acme_test_suites:
+            machine_for_this_test = parse_test_name(testarg)[4]
+            if machine_for_this_test is not None:
+                if machine is None:
+                    machine = machine_for_this_test
+                else:
+                    expect(machine == machine_for_this_test, "Must have consistent machine '%s' != '%s'" % (machine, machine_for_this_test))
+
+    return machine
+
 ###############################################################################
 def get_full_test_names(testargs, machine, compiler):
 ###############################################################################