diff --git a/WORKSPACE b/WORKSPACE
index 435f83bc62..826c846796 100644
--- a/WORKSPACE
+++ b/WORKSPACE
@@ -96,7 +96,10 @@ install_bazel_dependencies()
 git_repository(
     name = "build_bazel_rules_typescript",
     commit = "10a5a86885f95ab788fd841ade47b6a16e0c13d6",
-    patches = ["//:rules_typescript_pr_496.patch"],
+    patches = [
+        "//:rules_typescript_pr_494.patch",
+        "//:rules_typescript_pr_496.patch",
+    ],
     remote = "http://github.com/bazelbuild/rules_typescript.git",
     shallow_since = "1582757372 -0800",
 )
diff --git a/rules_typescript_pr_494.patch b/rules_typescript_pr_494.patch
new file mode 100644
index 0000000000..4f5d7617ea
--- /dev/null
+++ b/rules_typescript_pr_494.patch
@@ -0,0 +1,13 @@
+diff --git internal/common/module_mappings.bzl internal/common/module_mappings.bzl
+index b74e5b8..286c3b3 100644
+--- internal/common/module_mappings.bzl
++++ internal/common/module_mappings.bzl
+@@ -76,7 +76,7 @@ def get_module_mappings(label, attrs, srcs = [], workspace_name = None, mappings
+             workspace_name or label.workspace_root,
+             label.package,
+         ] if p])
+-        if attrs.module_root and attrs.module_root != ".":
++        if hasattr(attrs, "module_root") and attrs.module_root and attrs.module_root != ".":
+             mr = "%s/%s" % (mr, attrs.module_root)
+             if attrs.module_root.endswith(".ts"):
+                 if workspace_name: