diff --git a/index.d.ts b/index.d.ts
index 188895d2cd..543023ca71 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -1,5 +1,5 @@
 export interface AxiosTransformer {
-  (data: any): any;
+  (data?: any, headers?: any): any;
 }
 
 export interface AxiosAdapter {
diff --git a/lib/core/Axios.js b/lib/core/Axios.js
index f1af3e7bf6..ae01c67ec7 100644
--- a/lib/core/Axios.js
+++ b/lib/core/Axios.js
@@ -32,7 +32,7 @@ Axios.prototype.request = function request(config) {
     }, arguments[1]);
   }
 
-  config = utils.merge(defaults, this.defaults, { method: 'get' }, config);
+  config = utils.merge(defaults, this.defaults, {}, config);
   config.method = config.method.toLowerCase();
 
   // Hook up interceptors middleware
diff --git a/lib/defaults.js b/lib/defaults.js
index 9587b28b68..bf6493eb80 100644
--- a/lib/defaults.js
+++ b/lib/defaults.js
@@ -63,6 +63,8 @@ var defaults = {
     return data;
   }],
 
+  method: 'get',
+
   timeout: 0,
 
   xsrfCookieName: 'XSRF-TOKEN',