diff --git a/sdk/core/azure-common/testutils/common_recordingtestcase.py b/sdk/core/azure-common/testutils/common_recordingtestcase.py
index 8484b8805f30..ef12603075dc 100644
--- a/sdk/core/azure-common/testutils/common_recordingtestcase.py
+++ b/sdk/core/azure-common/testutils/common_recordingtestcase.py
@@ -66,7 +66,7 @@ def init_test_mode(self):
             self.test_mode = test_settings['mode']
         except:
             pass
-        
+
         if getattr(self, 'test_mode', None) is None:
             self.test_mode = TestMode.playback
 
@@ -134,11 +134,18 @@ def _scrub_sensitive_response_info(self, response):
             response = decode_response(response)
             headers = response.get('headers')
             if headers:
+                def internal_scrub(key, val):
+                    if key.lower() == 'retry-after':
+                        return '0'
+                    return self._scrub(val)
+
                 for name, val in headers.items():
-                    for i, e in enumerate(val):
-                        val[i] = self._scrub(e)
-                    if name.lower() == 'retry-after':
-                        val[:] = ['0']
+                    if isinstance(val, list):
+                        for i, e in enumerate(val):
+                            val[i] = internal_scrub(name, e)
+                    else:
+                        headers[name] = internal_scrub(name, val)
+
             body = response.get('body')
             if body:
                 body_str = body.get('string')
diff --git a/sdk/storage/azure-storage-blob/tests/testcase.py b/sdk/storage/azure-storage-blob/tests/testcase.py
index f2cc356b9df8..b52a611f4f92 100644
--- a/sdk/storage/azure-storage-blob/tests/testcase.py
+++ b/sdk/storage/azure-storage-blob/tests/testcase.py
@@ -328,9 +328,18 @@ def _scrub_sensitive_response_info(self, response):
             response = copy.deepcopy(response)
             headers = response.get('headers')
             if headers:
+                def internal_scrub(key, val):
+                    if key.lower() == 'retry-after':
+                        return '0'
+                    return self._scrub(val)
+
                 for name, val in headers.items():
-                    for i in range(len(val)):
-                        val[i] = self._scrub(val[i])
+                    if isinstance(val, list):
+                        for i, e in enumerate(val):
+                            val[i] = internal_scrub(name, e)
+                    else:
+                        headers[name] = internal_scrub(name, val)
+
             body = response.get('body')
             if body:
                 body_str = body.get('string')
diff --git a/sdk/storage/azure-storage-file/tests/filetestcase.py b/sdk/storage/azure-storage-file/tests/filetestcase.py
index b6bbe39fe956..087eb4708820 100644
--- a/sdk/storage/azure-storage-file/tests/filetestcase.py
+++ b/sdk/storage/azure-storage-file/tests/filetestcase.py
@@ -322,9 +322,18 @@ def _scrub_sensitive_response_info(self, response):
             response = copy.deepcopy(response)
             headers = response.get('headers')
             if headers:
+                def internal_scrub(key, val):
+                    if key.lower() == 'retry-after':
+                        return '0'
+                    return self._scrub(val)
+
                 for name, val in headers.items():
-                    for i in range(len(val)):
-                        val[i] = self._scrub(val[i])
+                    if isinstance(val, list):
+                        for i, e in enumerate(val):
+                            val[i] = internal_scrub(name, e)
+                    else:
+                        headers[name] = internal_scrub(name, val)
+
             body = response.get('body')
             if body:
                 body_str = body.get('string')
diff --git a/sdk/storage/azure-storage-queue/tests/queuetestcase.py b/sdk/storage/azure-storage-queue/tests/queuetestcase.py
index 98f9ca671aa9..2e96a22f0d54 100644
--- a/sdk/storage/azure-storage-queue/tests/queuetestcase.py
+++ b/sdk/storage/azure-storage-queue/tests/queuetestcase.py
@@ -346,9 +346,18 @@ def _scrub_sensitive_response_info(self, response):
             response = copy.deepcopy(response)
             headers = response.get('headers')
             if headers:
+                def internal_scrub(key, val):
+                    if key.lower() == 'retry-after':
+                        return '0'
+                    return self._scrub(val)
+
                 for name, val in headers.items():
-                    for i in range(len(val)):
-                        val[i] = self._scrub(val[i])
+                    if isinstance(val, list):
+                        for i, e in enumerate(val):
+                            val[i] = internal_scrub(name, e)
+                    else:
+                        headers[name] = internal_scrub(name, val)
+
             body = response.get('body')
             if body:
                 body_str = body.get('string')