With the assistance of Greek islanders, the Russian fleet was able to score a major victory against the Ottoman Navy in the Battle of Cesme, but this did not help the Greek army in Morea. As the Russians failed to bring the forces they promised, the revolt was soon crushed. Greek reinforcements from Macedonia and Olympus region faced opposition in their descent to Morea and thus were unable to assist the revolutionaries. Hard-pressed by the arising necessity to fight a major war with Russia on its northern borders, the Ottoman Empire hired Albanian mercenary troops and they defeated the Russo-Greek expedition at Tripolitsa.