Lawyers for Delphi Corp.’s unions and stakeholders tried to convince a bankruptcy judge Wednesday that letting the faltering auto parts company jettison its labor contracts would unfairly sideline them and risk a potentially ruinous strike.

But a Delphi executive countered that the power to cancel contracts — even if it triggers a walkout in coming months — is better than prolonging a staredown with unions that could further weaken its chances of survival.