With the end of his competitive swimming days approaching, Phelps himself has seemed nostalgic this week, talking about how he's been keeping a journal to commit his memories to paper.
"It's crazy that 20 years ago, I started swimming," Phelps told a group of children at a Boys & Girls Club earlier this week before competition began. "It started with a dream."
The appearance was part of Phelps' work on his charitable foundation, which promotes swimming and wellness for kids. He has long said he wanted not just to advance his own career but that of his sport, and the foundation is part of his portfolio as swimming's top ambassador. It's something he'll no doubt continue after his competition days end.
Fans and fellow swimmers alike, though, are relishing these final months of Phelps' racing days.
"He looks great," said Lindsay Mintenko, who as Lindsay Benko swam in the 2000 and 2004 Olympics with Phelps and remembers him as a "very goofy" yet focused 16-year-old.
Phelps said he and Mintenko were just reminiscing about seeing their names painted on the wall on either side of the Nat's diving platforms after they made their first Olympic teams. Both said reliving those memories has made what is likely Phelps' last race here special.
"I watched Michael grow up. He's always had the quiet confidence," said Mintenko, who won gold medals in both Olympics as part of the 200-meter freestyle relay team and now serves as the managing director of the U.S. national team. "He's a fierce competitor."