On 18 July, "Midilli" struck a mine; the ship took on some of water and was no longer able to escort coal convoys from Zonguldak to the Bosphorus. "Yavuz" was assigned to the task, and on 10 August she escorted a convoy of five coal transports, along with "Hamidiye" and three torpedo boats. During transit, the convoy was attacked by the Russian submarine "Tyulen", which sank one of the colliers. The following day, "Tyulen" and another submarine tried to attack "Yavuz" as well, though they were unable to reach a firing position. Two Russian destroyers, and , attacked a Turkish convoy escorted by "Hamidiye" and two torpedo boats on 5 September. "Hamidiye"s guns broke down during combat, and the Turks summoned "Yavuz", but she arrived too late: the Turkish colliers had already been beached to avoid capture by the Russian destroyers.