diff --git a/bin/docker-image-tool.sh b/bin/docker-image-tool.sh
index 071406336d1b..0d0f564bb8b9 100755
--- a/bin/docker-image-tool.sh
+++ b/bin/docker-image-tool.sh
@@ -57,6 +57,7 @@ function build {
   else
     # Not passed as an argument to docker, but used to validate the Spark directory.
     IMG_PATH="kubernetes/dockerfiles"
+    BUILD_ARGS=()
   fi
 
   if [ ! -d "$IMG_PATH" ]; then