Alexios Strategopoulos first appears in the chronicles in 1252-53, during the reign of John III Doukas Vatatzes, when he led a detachment of the army sent to plunder the areas of Nicaean's Greek rival, the Despotate of Epirus, around Lake Ostrovo. In 1254, he was based at Serres in Macedonia, and in the next year he participated, along with megas primmikerios Constantine Tornikes, in a campaign against the fortress of Tzepaina in the western Rhodope Mountains. The campaign failed with heavy losses. The contemporary historian George Akropolites puts the blame on the bad generalship shown by the two commanders, who failed to reconnoitre properly the Bulgarian forces opposing them. As a result, their army broke and fled leaving behind their equipment and horses to the Bulgarian shepherds and swineherds. This failure enraged the Nicaean emperor Theodore II Laskaris (r. 1254 - 1258), who removed both from their offices. In addition, probably because of Strategopoulos' close connection to the aristocratic faction around Michael Palaiologos, his son Constantine was blinded for lèse-majesté, and Strategopoulos himself was imprisoned some time later.