The decline is said to have begun on August 6, 1284, when the numerically superior fleet of Pisa, under the command of Albertino Morosini, was defeated by the brilliant tactics of the Genoese fleet, under the command of Benedetto Zaccaria and Oberto Doria, in the dramatic naval Battle of Meloria. This defeat ended the maritime power of Pisa and the town never fully recovered; in 1290, the Genoese destroyed forever the Porto Pisano (Pisa's port), and covered the land with salt. The region around Pisa did not permit the city to recover from the loss of thousands of sailors from the Meloria, while Liguria guaranteed enough sailors to Genoa. Goods, however, continued to be traded, albeit in reduced quantity, but the end came when the Arno started to change course, preventing the galleys from reaching the city's port up the river. The nearby area also likely became infested with malaria. The true end came in 1324, when Sardinia was entirely lost to the Aragonese.