The following month, on 5–6 December, "Yavuz" and "Midilli" provided protection for troop transports, and on 10 December, "Yavuz" bombarded Batum. On 23 December, "Yavuz" and the protected cruiser escorted three transports to Trebizond. While returning from another transport escort operation on 26 December, "Yavuz" struck a mine that exploded beneath the conning tower, on the starboard side, about one nautical mile outside the Bosphorus. The explosion tore a hole in the ship's hull, but the torpedo bulkhead held. Two minutes later, "Yavuz" struck a second mine on the port side, just forward of the main battery wing barbette; this tore open a hole. The bulkhead bowed in but retained watertight protection of the ship's interior. However, some 600 tons of water flooded the ship. There was no dock in the Ottoman Empire large enough to service "Yavuz", so temporary repairs were effected inside steel cofferdams, which were pumped out to create a dry work area around the damaged hull. The holes were patched with concrete, which held for several years before more permanent work was necessary.