Michael Phelps has peaked at right time

When Michael Phelps arrived in Rio as a 31-year-old swimmer who retired once and endured plenty of turmoil away from the pool, everyone wondered just how many gold medals was a realistic goal.

How does six sound?

In his first appearance of these Summer Games, Phelps showed he is still capable of the kind of jaw-dropping, did-he-really-just-do-that? performances that already made him the most decorated Olympic athlete of them all.