How to use mock in a private static final variable in Spock?

Question

Say I have a private static final variable in a Java class like:

@Service
public class MyClass {
    private static final Logger LOGGER = LoggerFactory.getLogger(MyClass.class);
    ...
}

Then I have test class like:

class MyClassTest extends Specification {

  @Autowired
  MyClass sut

  def "Testing a private static final variable"() {
    given:
    sut.LOGGER = Mock(Logger)

    when:
    ...
}

How can I use Mock(Logger) with sut.LOGGER where LOGGER is a private static final in MyClass class? Without the final keyword, the test would just run fine though but I wanted it to work with a final keyword. Any suggestion is highly appreciated.