diff --git a/Gopkg.lock b/Gopkg.lock
index 8dc9ecc3..5defcb1b 100644
--- a/Gopkg.lock
+++ b/Gopkg.lock
@@ -623,18 +623,20 @@
   revision = "80063a038e333bbe006c878e4c5ce4c74d055498"
 
 [[projects]]
-  digest = "1:ffb498178a6bbe5a877e715cc85a40d5a712883d85f5bf05acf26dbd6c8f71e2"
+  digest = "1:b48dee7800c8bfabca8663f14affbc537a075986e1fd7dcd402d71601518fa31"
   name = "google.golang.org/grpc"
   packages = [
     ".",
+    "attributes",
+    "backoff",
     "balancer",
     "balancer/base",
+    "balancer/grpclb/state",
     "balancer/roundrobin",
     "binarylog/grpc_binarylog_v1",
     "codes",
     "connectivity",
     "credentials",
-    "credentials/internal",
     "encoding",
     "encoding/proto",
     "grpclog",
@@ -642,26 +644,32 @@
     "internal/backoff",
     "internal/balancerload",
     "internal/binarylog",
+    "internal/buffer",
     "internal/channelz",
+    "internal/credentials",
     "internal/envconfig",
+    "internal/grpclog",
     "internal/grpcrand",
     "internal/grpcsync",
+    "internal/grpcutil",
+    "internal/resolver/dns",
+    "internal/resolver/passthrough",
+    "internal/serviceconfig",
+    "internal/status",
     "internal/syscall",
     "internal/transport",
     "keepalive",
     "metadata",
-    "naming",
     "peer",
     "resolver",
-    "resolver/dns",
-    "resolver/passthrough",
+    "serviceconfig",
     "stats",
     "status",
     "tap",
   ]
   pruneopts = "NUT"
-  revision = "25c4f928eaa6d96443009bd842389fb4fa48664e"
-  version = "v1.20.1"
+  revision = "a767afcb69f50a47471acd75d5a1ad062561554d"
+  version = "v1.33.1"
 
 [[projects]]
   digest = "1:85ce4b06f191dd616ad7f4377843ea08db7db003757bd0a67e1b3ac4cbd5c2ef"