Fix the oversight from #18841
diff --git a/tools/interop_matrix/client_matrix.py b/tools/interop_matrix/client_matrix.py
index 36f926d..6b6502b 100644
--- a/tools/interop_matrix/client_matrix.py
+++ b/tools/interop_matrix/client_matrix.py
@@ -266,8 +266,8 @@
         ('v1.15.0', ReleaseInfo(testcases_file='csharp__v1.3.9')),
         ('v1.16.0', ReleaseInfo(testcases_file='csharp__v1.3.9')),
         ('v1.17.1', ReleaseInfo(testcases_file='csharp__v1.3.9')),
-        ('v1.18.0', ReleaseInfo(testcases_file='csharpcoreclr__v1.18.0')),
-        ('v1.19.0', ReleaseInfo(testcases_file='csharpcoreclr__v1.18.0')),
+        ('v1.18.0', ReleaseInfo(testcases_file='csharp__v1.18.0')),
+        ('v1.19.0', ReleaseInfo(testcases_file='csharp__v1.18.0')),
         ('v1.20.0', ReleaseInfo()),
     ]),
 }
diff --git a/tools/interop_matrix/testcases/csharp__v1.18.0 b/tools/interop_matrix/testcases/csharp__v1.18.0
new file mode 100755
index 0000000..3ca145e
--- /dev/null
+++ b/tools/interop_matrix/testcases/csharp__v1.18.0
@@ -0,0 +1,22 @@
+#!/bin/bash
+# DO NOT MODIFY
+# This file is generated by run_interop_tests.py/create_testcases.sh
+echo "Testing ${docker_image:=grpc_interop_csharpcoreclr:bae17a7e-5450-4781-8982-e82cb89db6dd}"
+docker run -i --rm=true -w /var/local/git/grpc/src/csharp/Grpc.IntegrationTesting.Client/bin/Debug/netcoreapp1.1 --net=host $docker_image bash -c "dotnet exec Grpc.IntegrationTesting.Client.dll --server_host=grpc-test.sandbox.googleapis.com --server_port=443 --test_case=large_unary --use_tls=true"
+docker run -i --rm=true -w /var/local/git/grpc/src/csharp/Grpc.IntegrationTesting.Client/bin/Debug/netcoreapp1.1 --net=host $docker_image bash -c "dotnet exec Grpc.IntegrationTesting.Client.dll --server_host=grpc-test.sandbox.googleapis.com --server_port=443 --test_case=empty_unary --use_tls=true"
+docker run -i --rm=true -w /var/local/git/grpc/src/csharp/Grpc.IntegrationTesting.Client/bin/Debug/netcoreapp1.1 --net=host $docker_image bash -c "dotnet exec Grpc.IntegrationTesting.Client.dll --server_host=grpc-test.sandbox.googleapis.com --server_port=443 --test_case=ping_pong --use_tls=true"
+docker run -i --rm=true -w /var/local/git/grpc/src/csharp/Grpc.IntegrationTesting.Client/bin/Debug/netcoreapp1.1 --net=host $docker_image bash -c "dotnet exec Grpc.IntegrationTesting.Client.dll --server_host=grpc-test.sandbox.googleapis.com --server_port=443 --test_case=empty_stream --use_tls=true"
+docker run -i --rm=true -w /var/local/git/grpc/src/csharp/Grpc.IntegrationTesting.Client/bin/Debug/netcoreapp1.1 --net=host $docker_image bash -c "dotnet exec Grpc.IntegrationTesting.Client.dll --server_host=grpc-test.sandbox.googleapis.com --server_port=443 --test_case=client_streaming --use_tls=true"
+docker run -i --rm=true -w /var/local/git/grpc/src/csharp/Grpc.IntegrationTesting.Client/bin/Debug/netcoreapp1.1 --net=host $docker_image bash -c "dotnet exec Grpc.IntegrationTesting.Client.dll --server_host=grpc-test.sandbox.googleapis.com --server_port=443 --test_case=server_streaming --use_tls=true"
+docker run -i --rm=true -w /var/local/git/grpc/src/csharp/Grpc.IntegrationTesting.Client/bin/Debug/netcoreapp1.1 --net=host $docker_image bash -c "dotnet exec Grpc.IntegrationTesting.Client.dll --server_host=grpc-test.sandbox.googleapis.com --server_port=443 --test_case=cancel_after_begin --use_tls=true"
+docker run -i --rm=true -w /var/local/git/grpc/src/csharp/Grpc.IntegrationTesting.Client/bin/Debug/netcoreapp1.1 --net=host $docker_image bash -c "dotnet exec Grpc.IntegrationTesting.Client.dll --server_host=grpc-test.sandbox.googleapis.com --server_port=443 --test_case=cancel_after_first_response --use_tls=true"
+docker run -i --rm=true -w /var/local/git/grpc/src/csharp/Grpc.IntegrationTesting.Client/bin/Debug/netcoreapp1.1 --net=host $docker_image bash -c "dotnet exec Grpc.IntegrationTesting.Client.dll --server_host=grpc-test.sandbox.googleapis.com --server_port=443 --test_case=timeout_on_sleeping_server --use_tls=true"
+docker run -i --rm=true -w /var/local/git/grpc/src/csharp/Grpc.IntegrationTesting.Client/bin/Debug/netcoreapp1.1 --net=host $docker_image bash -c "dotnet exec Grpc.IntegrationTesting.Client.dll --server_host=grpc-test4.sandbox.googleapis.com --server_port=443 --test_case=large_unary --use_tls=true"
+docker run -i --rm=true -w /var/local/git/grpc/src/csharp/Grpc.IntegrationTesting.Client/bin/Debug/netcoreapp1.1 --net=host $docker_image bash -c "dotnet exec Grpc.IntegrationTesting.Client.dll --server_host=grpc-test4.sandbox.googleapis.com --server_port=443 --test_case=empty_unary --use_tls=true"
+docker run -i --rm=true -w /var/local/git/grpc/src/csharp/Grpc.IntegrationTesting.Client/bin/Debug/netcoreapp1.1 --net=host $docker_image bash -c "dotnet exec Grpc.IntegrationTesting.Client.dll --server_host=grpc-test4.sandbox.googleapis.com --server_port=443 --test_case=ping_pong --use_tls=true"
+docker run -i --rm=true -w /var/local/git/grpc/src/csharp/Grpc.IntegrationTesting.Client/bin/Debug/netcoreapp1.1 --net=host $docker_image bash -c "dotnet exec Grpc.IntegrationTesting.Client.dll --server_host=grpc-test4.sandbox.googleapis.com --server_port=443 --test_case=empty_stream --use_tls=true"
+docker run -i --rm=true -w /var/local/git/grpc/src/csharp/Grpc.IntegrationTesting.Client/bin/Debug/netcoreapp1.1 --net=host $docker_image bash -c "dotnet exec Grpc.IntegrationTesting.Client.dll --server_host=grpc-test4.sandbox.googleapis.com --server_port=443 --test_case=client_streaming --use_tls=true"
+docker run -i --rm=true -w /var/local/git/grpc/src/csharp/Grpc.IntegrationTesting.Client/bin/Debug/netcoreapp1.1 --net=host $docker_image bash -c "dotnet exec Grpc.IntegrationTesting.Client.dll --server_host=grpc-test4.sandbox.googleapis.com --server_port=443 --test_case=server_streaming --use_tls=true"
+docker run -i --rm=true -w /var/local/git/grpc/src/csharp/Grpc.IntegrationTesting.Client/bin/Debug/netcoreapp1.1 --net=host $docker_image bash -c "dotnet exec Grpc.IntegrationTesting.Client.dll --server_host=grpc-test4.sandbox.googleapis.com --server_port=443 --test_case=cancel_after_begin --use_tls=true"
+docker run -i --rm=true -w /var/local/git/grpc/src/csharp/Grpc.IntegrationTesting.Client/bin/Debug/netcoreapp1.1 --net=host $docker_image bash -c "dotnet exec Grpc.IntegrationTesting.Client.dll --server_host=grpc-test4.sandbox.googleapis.com --server_port=443 --test_case=cancel_after_first_response --use_tls=true"
+docker run -i --rm=true -w /var/local/git/grpc/src/csharp/Grpc.IntegrationTesting.Client/bin/Debug/netcoreapp1.1 --net=host $docker_image bash -c "dotnet exec Grpc.IntegrationTesting.Client.dll --server_host=grpc-test4.sandbox.googleapis.com --server_port=443 --test_case=timeout_on_sleeping_server --use_tls=true"