diff --git a/modules/__tests__/withRouter-test.js b/modules/__tests__/withRouter-test.js
index d276ce28fd..06ade17b4b 100644
--- a/modules/__tests__/withRouter-test.js
+++ b/modules/__tests__/withRouter-test.js
@@ -4,21 +4,17 @@ import { render, unmountComponentAtNode } from 'react-dom'
 import createHistory from '../createMemoryHistory'
 import Route from '../Route'
 import Router from '../Router'
-import routerShape from '../PropTypes'
 import withRouter from '../withRouter'
 
 describe('withRouter', function () {
-  class App extends Component {
-    propTypes: {
-      router: routerShape.isRequired
-    }
-    testFunction() {
-      return 'hello from the test function'
-    }
-    render() {
-      expect(this.props.router).toExist()
-      return <h1>App</h1>
-    }
+  const routerStub = {
+    push() {},
+    replace() {},
+    go() {},
+    goBack() {},
+    goForward() {},
+    setRouteLeaveHook() {},
+    isActive() {}
   }
 
   let node
@@ -30,51 +26,63 @@ describe('withRouter', function () {
     unmountComponentAtNode(node)
   })
 
-  it('puts router on context', function (done) {
-    const WrappedApp = withRouter(App)
+  it('should put router on props', function (done) {
+    const MyComponent = withRouter(({ router }) => {
+      expect(router).toExist()
+      done()
+      return null
+    })
+
+    function App() {
+      return <MyComponent /> // Ensure no props are passed explicitly.
+    }
 
     render((
       <Router history={createHistory('/')}>
-        <Route path="/" component={WrappedApp} />
+        <Route path="/" component={App} />
       </Router>
-    ), node, function () {
-      done()
-    })
+    ), node)
   })
 
-  it('still uses router prop if provided', function (done) {
-    const Test = withRouter(function (props) {
-      props.test(props)
+  it('should set displayName', function () {
+    function MyComponent() {
       return null
-    })
-    const router = {
-      push() {},
-      replace() {},
-      go() {},
-      goBack() {},
-      goForward() {},
-      setRouteLeaveHook() {},
-      isActive() {}
-    }
-    const test = function (props) {
-      expect(props.router).toBe(router)
     }
 
-    render(<Test router={router} test={test} />, node, done)
+    MyComponent.displayName = 'MyComponent'
+
+    expect(withRouter(MyComponent).displayName)
+      .toEqual('withRouter(MyComponent)')
+  })
+
+  it('should use router prop if specified', function (done) {
+    const MyComponent = withRouter(({ router }) => {
+      expect(router).toBe(routerStub)
+      done()
+      return null
+    })
+
+    render(<MyComponent router={routerStub} />, node)
   })
 
-  it('should support withRefs as a parameter', function (done) {
-    const WrappedApp = withRouter(App, { withRef: true })
-    const router = {
-      push() {},
-      replace() {},
-      go() {},
-      goBack() {},
-      goForward() {},
-      setRouteLeaveHook() {},
-      isActive() {}
+  it('should support withRef', function () {
+    const spy = expect.createSpy()
+
+    class MyComponent extends Component {
+      invokeSpy() {
+        spy()
+      }
+
+      render() {
+        return null
+      }
     }
-    const component = render((<WrappedApp router={router}/>), node, done)
-    expect(component.getWrappedInstance().testFunction()).toEqual('hello from the test function')
+
+    const WrappedComponent = withRouter(MyComponent, { withRef: true })
+
+    const instance = render(<WrappedComponent router={routerStub} />, node)
+    instance.getWrappedInstance().invokeSpy()
+
+    expect(spy).toHaveBeenCalled()
   })
 })
diff --git a/modules/withRouter.js b/modules/withRouter.js
index d5c6eb2b2c..b56fdc0946 100644
--- a/modules/withRouter.js
+++ b/modules/withRouter.js
@@ -1,31 +1,38 @@
+import invariant from 'invariant'
 import React from 'react'
 import hoistStatics from 'hoist-non-react-statics'
 import { routerShape } from './PropTypes'
-import warning from './routerWarning'
-
 
 function getDisplayName(WrappedComponent) {
   return WrappedComponent.displayName || WrappedComponent.name || 'Component'
 }
 
 export default function withRouter(WrappedComponent, options) {
-  const { withRef } = options || {}
+  const withRef = options && options.withRef
 
   const WithRouter = React.createClass({
     contextTypes: { router: routerShape },
     propTypes: { router: routerShape },
 
     getWrappedInstance() {
-      warning(withRef, 'To access the wrappedInstance you must provide { withRef: true } as the second argument of the withRouter call')
-      return this.wrappedComponent
+      invariant(
+        withRef,
+        'To access the wrapped instance, you need to specify ' +
+        '`{ withRef: true }` as the second argument of the withRouter() call.'
+      )
+
+      return this.wrappedInstance
     },
 
     render() {
-      const { router, ...props } = this.props
+      const router = this.props.router || this.context.router
+      const props = { ...this.props, router }
 
-      if (withRef) props.ref = component =>this.wrappedComponent = component
+      if (withRef) {
+        props.ref = (c) => { this.wrappedInstance = c }
+      }
 
-      return <WrappedComponent {...props} router={router || this.context.router} />
+      return <WrappedComponent {...props} />
     }
   })