Spring security 5.20 + SAML2

Question

Is it possible to start a SAML2 authentication process restricting to certain URLs? So my idea is to use a URL like /saml2login that launches all the SAML authentication process.

I've tr¡ed with something similar to:

  httpSecurity.authorizeRequests()
                .antMatchers("/saml2login").authenticated()
                .and()
                .saml2Login()
                .relyingPartyRegistrationRepository(
                        new InMemoryRelyingPartyRegistrationRepository(
                                getSaml2AuthenticationConfiguration()
                        )
                );

But It doesn't work