MethodNotAllowedHttpException when testing on Lumen 5.6

I am testing a Lumen 5.6 API .

Here is my route:

$router->delete('/tournaments/{slug}', 'TournamentController@destroy');

When consuming with Angular 6, I have no problem, route is working, but when I try to test with PHPUnit with:

$this->call('DELETE', '/tournaments/' . $tournament->slug);

I get a MethodNotAllowedHttpException

Why ?