カラブリア沖海戦
On 27 June, together with the destroyers and , she sank the south east of Crete. "Defender" participated in the Battle of Calabria on 9 July as an escort for the heavy ships of Force C and unsuccessfully engaged Italian destroyers without suffering any damage. Together with her sisters "Dainty" and , the Australian destroyer , and the light cruisers and , she escorted Convoy AN.2 from Egypt to various ports in the Aegean Sea in late July.