Antony probably did not know about the death of Hirtius or understand the weakness of the legions left to Octavian's command. Rather than contemplating a decisive counterattack, Antony feared a renewed attack on his own camps. He therefore adopted Julius Caesar's expedient after the failure at the Battle of Gergovia and abandoned the siege, hoping to join up with the legions that Ventidius Bassus was bringing from Picenum. Having reconcentrated his forces, he proceeded to march to the Alps to communicate with the Caesarian leaders Marcus Aemilius Lepidus in Gallia Narbonensis and Lucius Munatius Plancus in Gallia Comata. After making his decision, Mark Antony acted swiftly and effectively: the very night after the battle, he sent a message instructing Ventidius Bassus to march quickly through the Apennines and join him with his three legions. He then abandoned the siege on the morning of 22 April 43 BC, retiring with all his surviving forces. In a few days, marching west along the Via Aemilia, his legions reached first Parma and then Placentia without difficulty, for his opponents had remained in Mutina, leaving Antony to gain two days' advantage. Arriving at Tortona, Mark Antony decided to turn southwards and crossed his four legions over the Apennines. In this way, he reached the coast of Liguria west of Genoa at Vada Sabatia, where on 3 May 43 BC, he was joined by Ventidius Bassus with three legions. Antony's lieutenant had not encountered any check to his progress through the mountains to the Ligurian coast; thus, Antony's manoeuvre to extricate himself from Mutina and regrouping proved successful.