boilers. World War I Panteleimon, flagship of the 1st Battleship Brigade, accompanied by the pre-dreadnoughts , , and Tri Sviatitelia, covered the pre-dreadnought Rostislav while she bombarded Trebizond on the morning of 17 November 1914. They were intercepted the following day by the Ottoman battlecruiser Yavuz Sultan Selim (the ex-German ) and the light cruiser Midilli (the ex-German ) on their return voyage to Sevastopol in what came to be known as the Battle of Cape Sarych. Despite the noon hour the conditions were foggy; the capital ships initially did not spot each other. Although several other ships opened fire, hitting the Yavuz Sultan Selim once, Panteleimon held her fire because her turrets could not see the Ottoman ships before they disengaged. Tri Sviatitelia and Rostislav bombarded Ottoman fortifications at the mouth of the Bosphorus on 18 March 1915, the first of several attacks intended to divert troops and attention from the ongoing Gallipoli campaign, but fired only 105 rounds before sailing north to rejoin Panteleimon, Ioann Zlatoust and Evstafi. Tri Sviatitelia and Rostislav were intended to repeat the bombardment the following day, but were hindered by heavy fog. On 3 April, Yavuz Sultan Selim and several ships of the Ottoman navy raided the Russian port at Odessa; the Russian battleship squadron sortied to intercept them. The battleships pursued Yavuz Sultan Selim the entire day, but were unable to close to effective gunnery range and were forced to break off the chase. On 25 April Tri Sviatitelia and Rostislav repeated their bombardment of the Bosphorus forts. Tri Sviatitelia, Rostislav and Panteleimon bombarded the forts again on 2 and 3 May. This time a total of 337 main-gun rounds were fired in addition to 528 six-inch shells between the three battleships. On 9 May 1915, Tri Sviatitelia and Panteleimon returned to bombard the Bosphorus forts, covered by the remaining pre-dreadnoughts. Yavuz Sultan Selim intercepted the three ships of the covering force, although no damage was inflicted by either side. Tri Sviatitelia and Pantelimon rejoined their consorts and the latter scored two hits on Yavuz Sultan Selim before it broke off the action. The Russian ships pursued it for six hours before giving up the chase. On 1 August, all of the Black Sea pre-dreadnoughts were transferred to the 2nd Battleship Brigade, after the more powerful dreadnought entered service. On 1 October the new dreadnought provided cover while Ioann Zlatoust and Pantelimon