Lestock, his second in command, was also a skilful officer; but the two were on bad terms, and when, in February, 1744, Matthews attacked the Spanish fleet, Lestock disobeyed his signals, and by his misconduct deprived Matthews of a splendid victory, which was clearly within his grasp.

On one occasion, while the Viceroy, accompanied by Matthews, Cowan, and other commanders, was riding to view the country, a horseman approached them under cover of a cactus hedge, and threw his lance, wounding Matthews in the thigh.