diff --git a/client/client.go b/client/client.go
index 0108471c..77568dd6 100644
--- a/client/client.go
+++ b/client/client.go
@@ -52,7 +52,7 @@ type Requester interface {
 
 	// Transport provides direct access to the transport instance for
 	// specialist operations.
-	Transport() http.RoundTripper
+	Transport() *http.Transport
 }
 
 // RequestOptions allows setting up a specific request.
@@ -198,16 +198,11 @@ func (client *Client) getTaskWebsocket(taskID, websocketID string) (clientWebsoc
 	return client.getWebsocket(url)
 }
 
-func getWebsocket(transport http.RoundTripper, url string) (clientWebsocket, error) {
-	httpTransport, ok := transport.(*http.Transport)
-	if !ok {
-		return nil, fmt.Errorf("cannot create websocket: transport not compatible")
-	}
-
+func getWebsocket(transport *http.Transport, url string) (clientWebsocket, error) {
 	dialer := websocket.Dialer{
-		NetDial:          httpTransport.Dial,
-		Proxy:            httpTransport.Proxy,
-		TLSClientConfig:  httpTransport.TLSClientConfig,
+		NetDial:          transport.Dial,
+		Proxy:            transport.Proxy,
+		TLSClientConfig:  transport.TLSClientConfig,
 		HandshakeTimeout: 5 * time.Second,
 	}
 	conn, _, err := dialer.Dial(url, nil)
@@ -216,16 +211,7 @@ func getWebsocket(transport http.RoundTripper, url string) (clientWebsocket, err
 
 // CloseIdleConnections closes any API connections that are currently unused.
 func (client *Client) CloseIdleConnections() {
-	transport := client.Requester().Transport()
-	// The following is taken from net/http/client.go because
-	// we are directly going to try and close idle connections and
-	// we must make sure the transport supports this.
-	type closeIdler interface {
-		CloseIdleConnections()
-	}
-	if tr, ok := transport.(closeIdler); ok {
-		tr.CloseIdleConnections()
-	}
+	client.Requester().Transport().CloseIdleConnections()
 }
 
 // Maintenance returns an error reflecting the daemon maintenance status or nil.
@@ -589,7 +575,7 @@ type DefaultRequester struct {
 	baseURL   url.URL
 	doer      doer
 	userAgent string
-	transport http.RoundTripper
+	transport *http.Transport
 	decoder   DecoderFunc
 }
 
@@ -625,6 +611,6 @@ func (br *DefaultRequester) SetDecoder(decoder DecoderFunc) {
 	br.decoder = decoder
 }
 
-func (br *DefaultRequester) Transport() http.RoundTripper {
+func (br *DefaultRequester) Transport() *http.Transport {
 	return br.transport
 }