Ottoman-Habsburg wars
In 1529, Ottoman corsair Hayreddin Barbarossa conquered the Peñón of Algiers, turning it into a base of Barbary privateering. Months later, Portuondo, now General-Captain of Granada, fell unexpectedly against Barbarossa's lieutenant Aydın Reis, due to which Bazán was promoted to his captaincy. In August 1532, with a fleet of ten galleys and 2,000 soldiers, Bazán captured the city of Honaine, another of Barbarossa's ports. Returning with much booty and 1,000 prisoners, he used them to increase the number of galleys under his command up to 15. Bazán's presence dissuaded Aydin and Sinan Reis from acting freely in Spanish waters, although their attacks on European coasts to feed the lucrative Barbary slave trade continued being endemic.
In May 1533, Ottoman Sultan Suleiman the Magnificent issued a 110-ship fleet under Lütfi Pasha to besiege Corone, which grand imperial admiral Andrea Doria had conquered the previous year while sacking the Ottoman Peloponnese. Bazán contributed to Doria's relief fleet with 12 galleys of his own making, although they eventually did not join the fleet, staying in Messina possibly to watch for the movements of the French fleet of Marseille. Doria still managed to lift the siege. The same year, Bazán captured Turkish privateer Jaban Arraez, who came recklessly against him with two galleys and six galiots.
Bazán also led the Spanish galleys during the conquest of Tunis in 1535, serving as Doria's lieutenant in the fleet. He explored the local defenses by staging a grand ruse, where he had his galley rush to the enemy port of La Goulette while pursued by the rest of the fleet, making it look like his ship had been seized by its rowing slaves. He then escaped La Goulette after firing his artillery point blank on the port. Bazán later headed the assault of La Goulette with the Spanish marine infantry, narrowly avoiding death by an arquebus shot which wounded him in the nose.
However, when Barbarossa fled Tunis, Bazán was passed over by Doria for the mission to chase the Turk, which was instead handed to his relatives Giannettino Doria and Adamo Centurione. They reached Hayreddin in Bonna, but upon finding him with a fleet in equal numbers to theirs, they turned tail without even blockading the harbor. When Doria arrived with reinforcements, Barbarossa had already fled to Algiers, which the fleet could not invade due to the autumn weather. Bazán was so disappointed with the lost chance that he vowed to quit from his job as soon as it would be possible, being also embittered by his usual clashes with the grueling Spanish bureaucracy.