diff --git a/client/container_create.go b/client/container_create.go
index 9893579..bbef1c9 100644
--- a/client/container_create.go
+++ b/client/container_create.go
@@ -34,7 +34,7 @@ func (cli *Client) ContainerCreate(ctx context.Context, config *container.Config
 
 	serverResp, err := cli.post(ctx, "/containers/create", query, body, nil)
 	if err != nil {
-		if serverResp != nil && serverResp.statusCode == 404 && strings.Contains(err.Error(), "No such image") {
+		if serverResp.statusCode == 404 && strings.Contains(err.Error(), "No such image") {
 			return response, imageNotFoundError{config.Image}
 		}
 		return response, err
diff --git a/client/image_create.go b/client/image_create.go
index 6dfc039..1528b0b 100644
--- a/client/image_create.go
+++ b/client/image_create.go
@@ -28,7 +28,7 @@ func (cli *Client) ImageCreate(ctx context.Context, parentReference string, opti
 	return resp.body, nil
 }
 
-func (cli *Client) tryImageCreate(ctx context.Context, query url.Values, registryAuth string) (*serverResponse, error) {
+func (cli *Client) tryImageCreate(ctx context.Context, query url.Values, registryAuth string) (serverResponse, error) {
 	headers := map[string][]string{"X-Registry-Auth": {registryAuth}}
 	return cli.post(ctx, "/images/create", query, nil, headers)
 }
diff --git a/client/image_push.go b/client/image_push.go
index 89191ee..a30fc3b 100644
--- a/client/image_push.go
+++ b/client/image_push.go
@@ -48,7 +48,7 @@ func (cli *Client) ImagePush(ctx context.Context, ref string, options types.Imag
 	return resp.body, nil
 }
 
-func (cli *Client) tryImagePush(ctx context.Context, imageID string, query url.Values, registryAuth string) (*serverResponse, error) {
+func (cli *Client) tryImagePush(ctx context.Context, imageID string, query url.Values, registryAuth string) (serverResponse, error) {
 	headers := map[string][]string{"X-Registry-Auth": {registryAuth}}
 	return cli.post(ctx, "/images/"+imageID+"/push", query, nil, headers)
 }
diff --git a/client/image_search.go b/client/image_search.go
index 3940dfd..b7a7de3 100644
--- a/client/image_search.go
+++ b/client/image_search.go
@@ -45,7 +45,7 @@ func (cli *Client) ImageSearch(ctx context.Context, term string, options types.I
 	return results, err
 }
 
-func (cli *Client) tryImageSearch(ctx context.Context, query url.Values, registryAuth string) (*serverResponse, error) {
+func (cli *Client) tryImageSearch(ctx context.Context, query url.Values, registryAuth string) (serverResponse, error) {
 	headers := map[string][]string{"X-Registry-Auth": {registryAuth}}
 	return cli.get(ctx, "/images/search", query, headers)
 }
diff --git a/client/login.go b/client/login.go
index 482f947..b14f239 100644
--- a/client/login.go
+++ b/client/login.go
@@ -14,7 +14,7 @@ import (
 func (cli *Client) RegistryLogin(ctx context.Context, auth types.AuthConfig) (types.AuthResponse, error) {
 	resp, err := cli.post(ctx, "/auth", url.Values{}, auth, nil)
 
-	if resp != nil && resp.statusCode == http.StatusUnauthorized {
+	if resp.statusCode == http.StatusUnauthorized {
 		return types.AuthResponse{}, unauthorizedError{err}
 	}
 	if err != nil {
diff --git a/client/plugin_install.go b/client/plugin_install.go
index 3f5e59f..6cf50ff 100644
--- a/client/plugin_install.go
+++ b/client/plugin_install.go
@@ -53,7 +53,7 @@ func (cli *Client) PluginInstall(ctx context.Context, name string, options types
 	return cli.PluginEnable(ctx, name)
 }
 
-func (cli *Client) tryPluginPull(ctx context.Context, query url.Values, registryAuth string) (*serverResponse, error) {
+func (cli *Client) tryPluginPull(ctx context.Context, query url.Values, registryAuth string) (serverResponse, error) {
 	headers := map[string][]string{"X-Registry-Auth": {registryAuth}}
 	return cli.post(ctx, "/plugins/pull", query, nil, headers)
 }
diff --git a/client/request.go b/client/request.go
index d6ad9f9..9cbb2b9 100644
--- a/client/request.go
+++ b/client/request.go
@@ -25,47 +25,47 @@ type serverResponse struct {
 }
 
 // head sends an http request to the docker API using the method HEAD.
-func (cli *Client) head(ctx context.Context, path string, query url.Values, headers map[string][]string) (*serverResponse, error) {
+func (cli *Client) head(ctx context.Context, path string, query url.Values, headers map[string][]string) (serverResponse, error) {
 	return cli.sendRequest(ctx, "HEAD", path, query, nil, headers)
 }
 
 // getWithContext sends an http request to the docker API using the method GET with a specific go context.
-func (cli *Client) get(ctx context.Context, path string, query url.Values, headers map[string][]string) (*serverResponse, error) {
+func (cli *Client) get(ctx context.Context, path string, query url.Values, headers map[string][]string) (serverResponse, error) {
 	return cli.sendRequest(ctx, "GET", path, query, nil, headers)
 }
 
 // postWithContext sends an http request to the docker API using the method POST with a specific go context.
-func (cli *Client) post(ctx context.Context, path string, query url.Values, obj interface{}, headers map[string][]string) (*serverResponse, error) {
+func (cli *Client) post(ctx context.Context, path string, query url.Values, obj interface{}, headers map[string][]string) (serverResponse, error) {
 	return cli.sendRequest(ctx, "POST", path, query, obj, headers)
 }
 
-func (cli *Client) postRaw(ctx context.Context, path string, query url.Values, body io.Reader, headers map[string][]string) (*serverResponse, error) {
+func (cli *Client) postRaw(ctx context.Context, path string, query url.Values, body io.Reader, headers map[string][]string) (serverResponse, error) {
 	return cli.sendClientRequest(ctx, "POST", path, query, body, headers)
 }
 
 // put sends an http request to the docker API using the method PUT.
-func (cli *Client) put(ctx context.Context, path string, query url.Values, obj interface{}, headers map[string][]string) (*serverResponse, error) {
+func (cli *Client) put(ctx context.Context, path string, query url.Values, obj interface{}, headers map[string][]string) (serverResponse, error) {
 	return cli.sendRequest(ctx, "PUT", path, query, obj, headers)
 }
 
 // put sends an http request to the docker API using the method PUT.
-func (cli *Client) putRaw(ctx context.Context, path string, query url.Values, body io.Reader, headers map[string][]string) (*serverResponse, error) {
+func (cli *Client) putRaw(ctx context.Context, path string, query url.Values, body io.Reader, headers map[string][]string) (serverResponse, error) {
 	return cli.sendClientRequest(ctx, "PUT", path, query, body, headers)
 }
 
 // delete sends an http request to the docker API using the method DELETE.
-func (cli *Client) delete(ctx context.Context, path string, query url.Values, headers map[string][]string) (*serverResponse, error) {
+func (cli *Client) delete(ctx context.Context, path string, query url.Values, headers map[string][]string) (serverResponse, error) {
 	return cli.sendRequest(ctx, "DELETE", path, query, nil, headers)
 }
 
-func (cli *Client) sendRequest(ctx context.Context, method, path string, query url.Values, obj interface{}, headers map[string][]string) (*serverResponse, error) {
+func (cli *Client) sendRequest(ctx context.Context, method, path string, query url.Values, obj interface{}, headers map[string][]string) (serverResponse, error) {
 	var body io.Reader
 
 	if obj != nil {
 		var err error
 		body, err = encodeData(obj)
 		if err != nil {
-			return nil, err
+			return serverResponse{}, err
 		}
 		if headers == nil {
 			headers = make(map[string][]string)
@@ -76,8 +76,8 @@ func (cli *Client) sendRequest(ctx context.Context, method, path string, query u
 	return cli.sendClientRequest(ctx, method, path, query, body, headers)
 }
 
-func (cli *Client) sendClientRequest(ctx context.Context, method, path string, query url.Values, body io.Reader, headers map[string][]string) (*serverResponse, error) {
-	serverResp := &serverResponse{
+func (cli *Client) sendClientRequest(ctx context.Context, method, path string, query url.Values, body io.Reader, headers map[string][]string) (serverResponse, error) {
+	serverResp := serverResponse{
 		body:       nil,
 		statusCode: -1,
 	}
@@ -199,10 +199,10 @@ func encodeData(data interface{}) (*bytes.Buffer, error) {
 	return params, nil
 }
 
-func ensureReaderClosed(response *serverResponse) {
-	if response != nil && response.body != nil {
+func ensureReaderClosed(response serverResponse) {
+	if body := response.body; body != nil {
 		// Drain up to 512 bytes and close the body to let the Transport reuse the connection
-		io.CopyN(ioutil.Discard, response.body, 512)
+		io.CopyN(ioutil.Discard, body, 512)
 		response.body.Close()
 	}
 }