diff --git a/modules/caddyhttp/reverseproxy/reverseproxy.go b/modules/caddyhttp/reverseproxy/reverseproxy.go
index f062ef598..91c651bd1 100644
--- a/modules/caddyhttp/reverseproxy/reverseproxy.go
+++ b/modules/caddyhttp/reverseproxy/reverseproxy.go
@@ -695,6 +695,7 @@ func (h *Handler) proxyLoopIteration(r *http.Request, origReq *http.Request, w h
 		if userOps != nil {
 			userOps.ApplyToRequest(r)
 		}
+		normalizeWebsocketHeaders(r.Header)
 	}
 
 	// proxy the request to that upstream