Italian ironclad San Martino

Map showing the disposition of the fleets on 20 July

On 16 July, Persano took the Italian fleet out of Ancona, bound for Lissa, where they arrived on the 18th. With them, they brought troop transports carrying 3,000 soldiers; the Italian warships began bombarding the Austrian forts on the island, with the intention of landing the soldiers once the fortresses had been silenced. In response, the Austrian Navy sent the fleet under Tegetthoff to attack the Italian ships.[5] At that time, San Martino was assigned to the 2nd Division, under Persano, along with the ironclad Re d'Italia and the coastal defense ship Palestro.[6] After arriving off Lissa on the 18th,[2] Persano sent most of his ships to bombard the town of Vis, but Persano was unable to effect the landing.[7] The next morning, Persano ordered another attack; four ironclads would force the harbor defenses at Vis while San Martino and the rest of the fleet would attempt to suppress the outer fortifications. This second attack also proved to be a failure, but Persano decided to make a third attempt the next day. San Martino and the bulk of the fleet would again try to disable the outer forts in preparation for the landing.[8]

Before the Italians could begin the attack, the dispatch boat Esploratore arrived, bringing news of Tegetthoff's approach. Persano's fleet was in disarray; the three ships of Admiral Giovanni Vacca's 1st Division were three miles to the northeast from Persano's main force, and three other ironclads were further away to the west.[9] Persano immediately ordered his ships to form up with Vacca's, first in line abreast formation, and then in line ahead formation. San Martino was at the center of the Italian line.[10] Shortly before the action began, Persano decided to leave his flagship and transfer to Affondatore, though none of his subordinates on the other ships were aware of the change. They there thus left to fight as individuals without direction. More dangerously, by stopping Re d'Italia, he allowed a significant gap to open up between Vacca's three ships and the rest of the fleet.[11]

Tegetthoff took his fleet through the gap between Vacca's and Persano's ships, though he failed to ram any Italian vessels on the first pass. The Austrians then turned back toward Persano's ships, and took Re d'Italia, San Martino, and Palestro under heavy fire. San Martino initially engaged the unarmored ships of the Austrian 2nd Division, but as Re d'Italia became embroiled in the ensuing melee, San Martino's captain attempted to come to her aid, though the ship was unable to prevent the Austrian flagship, Erzherzog Ferdinand Max, from ramming and sinking her.[12] Tegetthoff immediately ordered his crew to lower boats to pick up the men in the water, but with San Martino fast approaching, he could not leave his ship a stationary target. He instead ordered the small aviso Kaiserin Elizabeth to pick up the Italian survivors, but she too came under fire and was forced to abandon the effort.[13]

During the battle, San Martino collided with Regina Maria Pia and had her ram bow twisted, causing leaks in her hull.[14] Shortly thereafter, Persano broke off the engagement to consolidate his forces, but his ships, low on coal and ammunition, and with badly demoralized crews, could not be rallied by Persano's half-hearted attempt to launch an attack. The Italian fleet began to withdraw, followed by the Austrians; as night began to fall, the opposing fleets disengaged completely, heading for Ancona and Pola, respectively.[15] San Martino had been hit numerous times, and had her side armor penetrated by one shell, which did not succeed in penetrating the timber backing. Twice during the engagement, the ship was set on fire by Austrian shells, though her crew was able to put the fires out.[14] After the battle, Vacca replaced Persano; he was ordered to attack the main Austrian naval base at Pola, but the war ended before the operation could be carried out.[16]

For the rest of her long career, San Martino served in a variety of roles, both in the main fleet and in Italy's colonial empire.[17] After the war, the Italian government slashed the naval budget so significantly that the fleet had great difficulty in mobilizing its ironclad squadron to attack the port of Civitavecchia in September 1870, as part of the wars of Italian unification. Instead, the ships were laid up and the sailors conscripted to man them were sent home.[18] Some time after 1866, the ship was rebuilt as a central battery ship, with most of her guns located in a central, armored casemate. Two other guns were placed in the bow as chase guns, with a third mounted as a stern chaser. At this time, her armament was also revised, to two 220 mm (8.7 in) guns in the bow and nine 8 in guns, four on each broadside and the last in the stern.[1]

San Martino took part in the annual 1888 fleet maneuvers, along with the ironclads Lepanto, Italia, Caio Duilio, and Enrico Dandolo, one protected cruiser, four torpedo cruisers, and numerous smaller vessels. The maneuvers consisted of close-order drills and a simulated attack on and defense of La Spezia.[19] Between 1888 and 1890, the ship had her barque rig replaced with military masts. By this time, she had been rearmed with eight 6 in (150 mm) guns in the casemate and several smaller guns for close-range defense against torpedo boats. These included five 4.7 in (120 mm) guns, four 57 mm (2.2 in) guns, and eight 37 mm (1.5 in) Hotchkiss revolver cannons. She also received three torpedo tubes.[1] In 1894, the ship was assigned to the Third Division of the Italian fleet, along with the newly commissioned protected cruiser Liguria and the torpedo cruiser Confienza.[20] The ship was stricken from the naval register in 1903 and thereafter broken up for scrap.[1]