What was the old man's struggle and how did he succeed?

The old man's struggle was both physical and emotional, but through tenacity and strength of will, he overcomes those obstacles and succeeds by bringing in the great fish. In some people's eyes, the old man may be seen to have failed, but in reality, he beat the odds in multiple ways. He fished alone, went further than anyone else dared, caught the marlin most men dream of, and in the end...... knew he'd accomplished what he set out to do.