diff --git a/http2/server.go b/http2/server.go
index e4a9f44..dff2bb8 100644
--- a/http2/server.go
+++ b/http2/server.go
@@ -3204,6 +3204,7 @@
 			panic(fmt.Sprintf("newWriterAndRequestNoBody(%+v): %v", msg.url, err))
 		}
 
+		sc.curHandlers++
 		go sc.runHandler(rw, req, sc.handler.ServeHTTP)
 		return promisedID, nil
 	}