Could Romania have reshaped the Black Sea war?

How capable was the Romanian Navy, and could it have made the Black Sea safer against the Soviet Navy?

It performed creditably with what it had, but probably could not secure the Black Sea alone; a more effective Axis coalition might have mattered, yet the required cooperation never materialized.

The Romanian Navy was capable within its limits but unable by itself to obtain all the means needed to make the Black Sea secure against the Soviet Navy. A more successful Axis maritime effort could have supported amphibious operations and altered supply routes. Italian naval forces joining Romanian and German units could have put the Soviet position under considerably greater pressure. The scenario depended on Germany reliably supporting allies and on those separated Axis forces reaching and cooperating with one another, which never happened.