diff --git a/tools/run_tests/performance/scenario_config.py b/tools/run_tests/performance/scenario_config.py
index 725ca299bd49b35d458d7b625ffc51b48e88f89b..e1c1bc65b6b48eb7928883cee6be483d052710db 100644
--- a/tools/run_tests/performance/scenario_config.py
+++ b/tools/run_tests/performance/scenario_config.py
@@ -219,6 +219,16 @@ class CXXLanguage:
           server_core_limit=1, async_server_threads=1,
           secure=secure)
 
+      yield _ping_pong_scenario(
+          'cpp_protobuf_async_client_sync_server_unary_qps_unconstrained_%s' %
+          (secstr),
+          rpc_type='UNARY',
+          client_type='ASYNC_CLIENT',
+          server_type='SYNC_SERVER',
+          unconstrained_client='async',
+          secure=secure,
+          categories=smoketest_categories + [SCALABLE])
+
       for rpc_type in ['unary', 'streaming']:
         for synchronicity in ['sync', 'async']:
           yield _ping_pong_scenario(
diff --git a/tools/run_tests/tests.json b/tools/run_tests/tests.json
index d831d6df0c37677bb7f051cbdf3cc37e35362bcb..d6624723ac668b4c130ae5b9db27908bce5e45b8 100644
--- a/tools/run_tests/tests.json
+++ b/tools/run_tests/tests.json
@@ -33574,6 +33574,27 @@
     "shortname": "json_run_localhost:cpp_generic_async_streaming_qps_one_server_core_secure", 
     "timeout_seconds": 180
   }, 
+  {
+    "args": [
+      "--scenarios_json", 
+      "{\"scenarios\": [{\"name\": \"cpp_protobuf_async_client_sync_server_unary_qps_unconstrained_secure\", \"warmup_seconds\": 0, \"benchmark_seconds\": 1, \"num_servers\": 1, \"server_config\": {\"async_server_threads\": 0, \"core_limit\": 0, \"security_params\": {\"use_test_ca\": true, \"server_host_override\": \"foo.test.google.fr\"}, \"server_type\": \"SYNC_SERVER\"}, \"client_config\": {\"client_type\": \"ASYNC_CLIENT\", \"security_params\": {\"use_test_ca\": true, \"server_host_override\": \"foo.test.google.fr\"}, \"payload_config\": {\"simple_params\": {\"resp_size\": 0, \"req_size\": 0}}, \"client_channels\": 64, \"async_client_threads\": 0, \"outstanding_rpcs_per_channel\": 100, \"rpc_type\": \"UNARY\", \"load_params\": {\"closed_loop\": {}}, \"histogram_params\": {\"max_possible\": 60000000000.0, \"resolution\": 0.01}}, \"num_clients\": 0}]}"
+    ], 
+    "boringssl": true, 
+    "ci_platforms": [
+      "linux"
+    ], 
+    "cpu_cost": 8, 
+    "defaults": "boringssl", 
+    "exclude_configs": [], 
+    "flaky": false, 
+    "language": "c++", 
+    "name": "json_run_localhost", 
+    "platforms": [
+      "linux"
+    ], 
+    "shortname": "json_run_localhost:cpp_protobuf_async_client_sync_server_unary_qps_unconstrained_secure", 
+    "timeout_seconds": 180
+  }, 
   {
     "args": [
       "--scenarios_json", 
@@ -33805,6 +33826,27 @@
     "shortname": "json_run_localhost:cpp_generic_async_streaming_qps_one_server_core_insecure", 
     "timeout_seconds": 180
   }, 
+  {
+    "args": [
+      "--scenarios_json", 
+      "{\"scenarios\": [{\"name\": \"cpp_protobuf_async_client_sync_server_unary_qps_unconstrained_insecure\", \"warmup_seconds\": 0, \"benchmark_seconds\": 1, \"num_servers\": 1, \"server_config\": {\"async_server_threads\": 0, \"core_limit\": 0, \"security_params\": null, \"server_type\": \"SYNC_SERVER\"}, \"client_config\": {\"client_type\": \"ASYNC_CLIENT\", \"security_params\": null, \"payload_config\": {\"simple_params\": {\"resp_size\": 0, \"req_size\": 0}}, \"client_channels\": 64, \"async_client_threads\": 0, \"outstanding_rpcs_per_channel\": 100, \"rpc_type\": \"UNARY\", \"load_params\": {\"closed_loop\": {}}, \"histogram_params\": {\"max_possible\": 60000000000.0, \"resolution\": 0.01}}, \"num_clients\": 0}]}"
+    ], 
+    "boringssl": true, 
+    "ci_platforms": [
+      "linux"
+    ], 
+    "cpu_cost": 8, 
+    "defaults": "boringssl", 
+    "exclude_configs": [], 
+    "flaky": false, 
+    "language": "c++", 
+    "name": "json_run_localhost", 
+    "platforms": [
+      "linux"
+    ], 
+    "shortname": "json_run_localhost:cpp_protobuf_async_client_sync_server_unary_qps_unconstrained_insecure", 
+    "timeout_seconds": 180
+  }, 
   {
     "args": [
       "--scenarios_json",