diff --git a/tools/run_tests/pre_build_csharp.sh b/tools/run_tests/pre_build_csharp.sh
index 42ff60bea220f38f4a8ee0c30f71ddf94d0a0125..06c8a83071b15777f26120c9671e31ab5e9f2622 100755
--- a/tools/run_tests/pre_build_csharp.sh
+++ b/tools/run_tests/pre_build_csharp.sh
@@ -35,6 +35,11 @@ cd $(dirname $0)/../../src/csharp
 
 root=`pwd`
 
+if [ -x "$(command -v nuget)" ]
+then
+  nuget restore Grpc.sln
+fi
+
 if [ -n "$NUGET" ]
 then
   $NUGET restore Grpc.sln