In 272 b.C. Rome established a new garrison in Locri Epizephyrii. And, at least for now, this was the only real consequence that the new situation, created after the defeat of Pyrrhus, caused to the ancient Locrian polis.

Rome, in fact, didn't demand too much from the cities of Magna Graecia of which it had recently acquired the control, exempting them from providing soldiers for its legions and only asking in exchange their military support through the supply of warships when Rome needed it. (Polybius, Histories, I 20, 14 and XII 5, 2; Livy, Ab Urbe Condita, XLII 48, 7)

Therefore Locri became socia navalis of Rome but still maintained all the characteristics of a Greek polis, keeping its independence and continuing to mint coin.
 

The occasion in which Locri had to show its loyalty to Rome took place very soon.

In 264 b.C., in fact, the city of Messene, under threat from the Carthaginian advance in Sicily, sought the help of Rome which, after a short time, stepped in by sending its troops on the island and thus starting the first clash with Carthage; clash that will last until 241 b.C. when, during the naval battle fought near the Aegadian islands, the Roman fleet destroyed a large part of the enemy fleet forcing Carthage to surrender.

During this period of time (more than two decades) it is not clear the role that the Greek cities of southern Italy played; but we know for sure, thanks to what has been handed down by Polybius, that Locri and the other cities supplied Rome with warships thus fulfilling the commitment made after the defeat of Pyrrhus. (Polybius, Histories, I 20, 7)

The only significant event of this period handed down by the historical sources about Locri is the one related to the raid and plunder of the Locrian territory made by the Carthaginian troops led by Hamilcar Barca (from his nickname "baraq", the thunderbolt). It's simply a brief record that Polybius has passed on us regarding the operations of the Carthaginian troops on the Brutium land during the eighteenth year of war (247 b.C.) which continues with the indication of the subsequent Carthaginians objectives in Sicily.

Here is the full version of the quoted passage: (Polybius, Histories, I 56, 1-3).

The role that Locri played in this historical phase was therefore very marginal (as opposed to what will happen during the Second Punic War). A few years after the quoted episode the First Punic War ended with the result that Rome had expanded its territory, adding the whole Sicily to it and better establishing its rule over the territories that it already controlled.

But the steady increase of the Roman influence started to raise a widespread discontent in the Greek cities of southern Italy, which showed by now signs of impatience against Rome. And Rome itself, during this period, started to show some distrust towards those cities where, in many cases, it decided to strengthen the garrisons already in place.

With such premises what will happen during the Second Punic War between Rome and the Greek cities will only be a result of the discontent built up during these years.