The scene is, in fact, the finale scene of the manga and anime. After 15 rounds of a World Bantamweight Championship bout between Yabuki Joe and the champion José Mendoza, where both fighters dealt severe concussion damage against each other, Joe silently sat on the corner as the beaten and scarred Mendoza is declared the winner, and is unresponsive when Tange Danpei went to told him the result.
Takamori Asao, the writer of the series, later confirmed that Joe has died due to severe concussion suffered throughout his boxing career, though the manga illustrator Chiba Tetsuya chose not to comment on Joe's fate, hinting that he might have survived. In the 1980 anime adaptation, the added scene concluded that Joe has indeed died.
The scene is known in Japan by the quote that Joe said to his coach Tange Danpei as he sat down; "I'm burnt out... into the ash..." ("燃え尽きたぜ...真っ白にな..." moetsukita ze... masshiro ni na.... Lit. "I'm burnt out... and turned white..."). The meme is used to represent that the character is completely tired from doing something, and/or has no regrets in doing so.
