diff --git a/common/components/Mojang/Api.php b/common/components/Mojang/Api.php
index 960a6bf..cb92122 100644
--- a/common/components/Mojang/Api.php
+++ b/common/components/Mojang/Api.php
@@ -4,7 +4,7 @@ namespace common\components\Mojang;
 use common\components\Mojang\exceptions\MojangApiException;
 use common\components\Mojang\exceptions\NoContentException;
 use common\components\Mojang\response\UsernameToUUIDResponse;
-use GuzzleHttp\Client as GuzzleClient;
+use Yii;
 
 class Api {
 
@@ -23,7 +23,7 @@ class Api {
             $query['atTime'] = $atTime;
         }
 
-        $response = $this->createClient()->get($this->buildUsernameToUUIDRoute($username), $query);
+        $response = $this->getClient()->get($this->buildUsernameToUUIDRoute($username), $query);
         if ($response->getStatusCode() === 204) {
             throw new NoContentException('Username not found');
         } elseif ($response->getStatusCode() !== 200) {
@@ -40,8 +40,11 @@ class Api {
         return $responseObj;
     }
 
-    protected function createClient() {
-        return new GuzzleClient();
+    /**
+     * @return \GuzzleHttp\Client
+     */
+    protected function getClient() {
+        return Yii::$app->guzzle;
     }
 
     protected function buildUsernameToUUIDRoute($username) {
diff --git a/tests/codeception/common/unit/components/Mojang/ApiTest.php b/tests/codeception/common/unit/components/Mojang/ApiTest.php
new file mode 100644
index 0000000..821bebc
--- /dev/null
+++ b/tests/codeception/common/unit/components/Mojang/ApiTest.php
@@ -0,0 +1,54 @@
+<?php
+namespace codeception\common\unit\components\Mojang;
+
+use common\components\Mojang\Api;
+use common\components\Mojang\response\UsernameToUUIDResponse;
+use GuzzleHttp\Client as GuzzleClient;
+use GuzzleHttp\Handler\MockHandler;
+use GuzzleHttp\HandlerStack;
+use GuzzleHttp\Psr7\Response;
+use tests\codeception\common\unit\TestCase;
+use Yii;
+
+class ApiTest extends TestCase {
+
+    /**
+     * @var MockHandler
+     */
+    private $handler;
+
+    public function _before() {
+        parent::_before();
+
+        $this->handler = new MockHandler();
+        $handler = HandlerStack::create($this->handler);
+        Yii::$app->set('guzzle', new GuzzleClient([
+            'handler' => $handler,
+        ]));
+    }
+
+    public function testUsernameToUUID() {
+        $this->handler->append(new Response(200, [], '{"id": "7125ba8b1c864508b92bb5c042ccfe2b","name": "KrisJelbring"}'));
+        $response = (new Api())->usernameToUUID('KrisJelbring');
+        $this->assertInstanceOf(UsernameToUUIDResponse::class, $response);
+        $this->assertEquals('7125ba8b1c864508b92bb5c042ccfe2b', $response->id);
+        $this->assertEquals('KrisJelbring', $response->name);
+    }
+
+    /**
+     * @expectedException \common\components\Mojang\exceptions\NoContentException
+     */
+    public function testUsernameToUUIDNoContent() {
+        $this->handler->append(new Response(204));
+        (new Api())->usernameToUUID('some-non-exists-user');
+    }
+
+    /**
+     * @expectedException \GuzzleHttp\Exception\RequestException
+     */
+    public function testUsernameToUUID404() {
+        $this->handler->append(new Response(404, [], '{"error":"Not Found","errorMessage":"The server has not found anything matching the request URI"}'));
+        (new Api())->usernameToUUID('#hashedNickname');
+    }
+
+}