diff --git a/DEPS b/DEPS
index 4e6066013ee..fab30228f6f 100644
--- a/DEPS
+++ b/DEPS
@@ -38,7 +38,7 @@ vars = {
 
   # Checked-in SDK version. The checked-in SDK is a Dart SDK distribution in a
   # cipd package used to run Dart scripts in the build and test infrastructure.
-  "sdk_tag": "version:2.9.0-10.0.dev",
+  "sdk_tag": "version:2.9.0-4.0.dev",
 
   # co19 is a cipd package. Use update.sh in tests/co19[_2] to update these
   # hashes. It requires access to the dart-build-access group, which EngProd