 The task for the Entente forces on the Macedonian front was to inflict major defeats on the Bulgarian army and effect a wide breakthrough in the Balkans in a relatively short time.The Allied command, which expected reinforcements, planned a major assault in the direction of Vardar and Doiran.In 1917 the 2nd (Bulgarian) Thracian Infantry Division was replaced at Doiran by the 9th Pleven Infantry division under the command of Colonel Vladimir Vazov.