An unexpected meeting
Neither Warren nor Joe wanted to meet up with each other after the events of 1973. Ironically, both change their minds and they are able to clear the air a little.
Irony of Warren
Warren may have been a star athlete who had everything he could have wanted but his personal life was ironically very chaotic and far from perfect. Up until his death, Warren was unable to form meaningful relationships with those around him, due to his arrogant personality.
Warren's guilt
Warren ironically went years denying any responsibility for what happened to Joe. However, just before he dies he has a change of heart and confesses he deliberately aimed for Castle's head when throwing the shot.
Irony of Joe Castle
When the narrator first introduces Joe Castle, he is a promising 21-year-old baseball player, who seemingly has the world at his feet. After breaking records in his first game, it seems that nothing is going to stop him. However, Castle's career is ironically cut short after a tragic accident.
Situational Irony
What happened to Joe Castle is an example of situational irony. This is because it is the last thing somebody would expect, after seeing his successful games in his first season. Nobody could have predicted the terrible accident he would have in 1973.