When the two Carthaginian leaders recognized the size of Regulus' army, they withdrew to a hill. This was a mistake, because here, their elephants were useless. The Romans defeated their opponents and proceeded to Tunis, close to Carthage. Negotiations were opened, and when these came to nothing, the Carthaginians replaced their two commanders by a Greek educated in Sparta, Xanthippus. He reorganized the army, and in 255, he defeated the Romans. Probably, Hasdrubal was one of his vice-commanders.
Although Hasdrubal had been partly responsible for the problems that Xanthippus had solved, the Carthaginians trusted him. In 255 or 254, he was sent to Sicily with an army that included 140 elephants. The exact date can unfortunately not be established, and we do not know where Hasdrubal was staying early in 254, when the Romans captured Panormus (Palermo). If he had crossed to Sicily in 255, he is to blame for another defeat; if he crossed later, his army was sent out as a counter-measure.
Anyhow, Hasdrubal proceeded to the walls of Panormus, where he was decisively defeated (251 or early 250). The Carthaginian leader returned to his home land, where he was executed. It was the last land battle between the two powers during the First Punic War.
The conflict lasted until 241, when the Roman navy defeated its enemy and Carthage was no longer able to muster a new fleet.