What techniques does santiago use to catch the marlin

Santiago takes his boat out far into the sea. He uses a line with bait fish (sardines and tuna) to lure the marlin to his hook. Once the marlin took the bait, Santiago allowed him to take the line and swim, waiting for the great fish to tire himself out. He suffers from cramping in his hand and continues to pull in other smaller fish for sustenance. His hand is bloodied and numb, but he continues to hold onto the line. Eventually, the marlin loses his ability to dive deep into the water and begins to circle, and once the marlin gets close enough..... Santiago finishes him off with the harpoon.