Saturday marked the halfway point of these Olympics Games, Day Eight of 16 in London that have so far rewarded the Americans and taunted Team Great Britain.
This weekend marked the transition from the Aquatics Centre to Olympic Stadium and the track.
Phelps dipped into a pool for the final time and British heptathlete Jessica Ennis fulfilled the national frenzy, the first of three Brits to win track and field gold medals.
"I think, obviously, to win three gold medals this evening has been unbelievable," Ennis said.
Britain is surging into the second half of the Games. Over two days, Ennis set a 100-meters hurdles world record (within a heptathlon), set a personal best in the 200-meter sprint, and gave up a lead in the 800 meters only to reclaim it in the home stretch with a triumphant sprint.
There's no separating Ennis from the very essence of these Games. But even she could be upstaged.
While Ennis competed in the long jump portion Saturday morning, the crowd was distracted by Oscar Pistorius and the gentle pinging he made as he ran, the first to do so at an Olympics on artificial legs. Surrounded by controversy and scrutiny, the South African glided into the semifinals of the men's 200 meters.
Later, Usain Bolt strolled through a morning qualifier more than half a second off his world record pace and everyone smirked.
So what will define the legacy and personality of these 30th Summer Games? Beijing had Phelps, Athens had history, Sydney had Rulon Gardner, Atlanta had tragedy, Barcelona had the Dream Team.
Has our moment happened, or will it smack us in these next eight days? Or is our moment not a moment at all?
It could be Phelps, of course, who on Saturday won his record-setting 22nd Olympic medal. Eighteen of those are gold, though that might have been 19 had he not eased up at the finish of the 200-meter butterfly and wound up with silver.
There's Gabrielle Douglas, the infectiously cheerful 16-year-old American gymnast who became the first African-American to win the individual all-around title.
Four years ago in Beijing, we knew the answer by this point. It was surely Phelps, who won eight gold medals, and not even Bolt's emergence could eclipse him.
But for Phelps, his latest record was an inevitability.
Not so with Douglas, who was a long shot to make the Olympics team even six months ago.
"She charged every single competition," national team director Martha Karolyi said this week. "She did better and better."
Then there is Britain itself, as on display as it has ever been, its temperament exposed at its first all-out Olympic Games. In 1908, London was forced into hosting the Games after Mt. Vesuvius erupted and pushed them out of Rome. And the 1948 Olympics, the first following World War II, were known as the "Austerity Games." This time around, friendlier-than-usual Brits greeted the world with "Harry Potter" author J.K. Rowling and former Beatle Paul McCartney perhaps the nation's two greatest living writers but quickly was thrown into a state of grouchiness before Team GB won its first gold.
London's a lot sunnier now at least within the confines of Olympic Park and surrounding venues.
Entering the second half of its Olympics, Great Britain has won 14 gold medals and is third in the overall medal count, behind China and the United States. It's well on its way to eclipsing its mark of 19 gold medals in Beijing, and has already surpassed the nine it won in Athens and the 11 Britons who brought gold medals home from Sydney.
Perhaps that is what Britain takes from this: As much gold as it ever has in the modern era, as if the Seven Cities of Gold were found in Stratford. But for us? For the rest of the world, these Games may have already been defined, the "moment" may have occurred.
But we can't see it yet.
There's a mountain in the way.
• At the halfway point of the Olympics, the U.S. has one fewer gold medal (25) and one fewer overall (53) than China.
• After a sluggish start that left Britons grumpy, "Team GB" dominated Saturday with three track and field golds.