diff --git a/modules/http-server/src/main/java/org/glassfish/grizzly/http/server/HttpServerFilter.java b/modules/http-server/src/main/java/org/glassfish/grizzly/http/server/HttpServerFilter.java
index 2ab201038..879f7305d 100644
--- a/modules/http-server/src/main/java/org/glassfish/grizzly/http/server/HttpServerFilter.java
+++ b/modules/http-server/src/main/java/org/glassfish/grizzly/http/server/HttpServerFilter.java
@@ -325,6 +325,10 @@ private NextAction afterService(final FilterChainContext ctx, final Connection c
 
         final HttpContext context = request.getRequest().getProcessingState().getHttpContext();
 
+        if (request.getRequest().isUpgrade() && !response.getResponse().isUpgrade()) {
+            request.getRequest().setIgnoreContentModifiers(false);
+        }
+
         httpRequestInProgress.remove(context);
         response.finish();
         request.onAfterService();