In 1941, she participated in Operation Grog, the shelling of Genoa, in operations against Vichy convoys and supporting air reinforcements to Malta. In May, "Sheffield" took part in the sinking of the , narrowly escaping a friendly fire torpedo attack by the aircraft carrier s Fairey Swordfish; Eleven torpedoes were dropped and only defective Duplex exploders and fine ship handling saved her from disaster. (In the report of the attack, Admiral Sir John Tovey, commanding Home Fleet, was told only no hits were scored on "Bismarck". The reaction of "Sheffield"s crew "has not made its way into the official records".) On 12 June, she located and sank one of "Bismarck"s tankers, "Friedrich Breme". After the destruction in early October 1941 of another German supply ship, "Kota Penang", (aided by the cruiser ), "Sheffield" returned to Britain.