LONDON -- As if 22 medal ceremonies over the last three Olympics weren't enough, Michael Phelps was summoned back to the pool deck for one more accolade.
This time, he received a trophy rather than a medal, an award that sought to sum up a career like no other.
"To Michael Phelps," it said, "the greatest Olympic athlete of all time."
Too bad it was silver.
Gold was the only color for this guy.
In a final race that was more a coronation than a contest, Phelps headed into retirement the only way imaginable -- with an 18th gold medal. Reclaiming the lead with his trademark butterfly stroke, the one seen in his Olympic debut as a 15-year-old in Sydney a dozen years ago, he capped off a mind-boggling career with a victory in the 4x100-meter medley relay Saturday.
"I've been able to do everything that I wanted," Phelps said.
When it was done, he hugged his teammates -- Matt Grevers, Brendan Hansen and Nathan Adrian -- before heading off the deck for the final time in his hip-hugging swimsuit. He waved to the crowd and smiled, clearly at peace with his decision to call it a career.
And what a career it was.
"I was able to really put the final cherry on top tonight, put all the whipped cream I wanted and sprinkles. I was able to top off the sundae," Phelps said. "It's been a great career. It's been a great journey. I can't be any more happy than I am."
Just three days after President Barack Obama called Phelps while traveling in Ohio, First Lady Michelle Obama took to Twitter to congratulate Phelps on his accomplishments.
"Wow @MichaelPhelps! Barack & I have been cheering you on! We're so proud of you & what you've accomplished. --mo," Obama tweeted Saturday.
Phelps retires with twice as many golds as any other Olympian, and his total of 22 medals is easily the best mark, too. He can be quite proud of his final Olympics as well, even though there were times he had trouble staying motivated after winning a record eight gold medals at the Beijing Games four years ago.
The 27-year-old could surely swim on for another Olympics, maybe two, but there's really no point.
"I told myself I never want to swim when I'm 30," Phelps said. "No offense to those people who are 30, but that was something I always said to myself, and that would be in three years. I just don't want to swim for those three years."
He hugged his longtime coach, Bob Bowman, who was teary eyed as he whispered three words that said it all, "I love you." Their partnership was formed 16 years ago, when Bowman took a gangly, hyperactive kid with an extraordinary gift and helped turn him into a swimmer the likes of which the world had never seen.
"Bob and I have somehow managed to do every single thing," Phelps said. "If you can say that about your career, there's no need to move forward. Time for other things."
Bouncing back from a disappointing first race in London, a fourth-place finish in the 400 individual medley, Phelps wound up with more medals than any other swimmer at the games: four golds and two silvers.
"Honestly, the first race kind of took the pressure off," Bowman said. "If it's not going to go too well, we should at least have fun while we're here. That helped us relax a little bit, then he started swimming well in the relays and he picked it up again."
Grevers had the Americans in front on the opening backstroke leg, but Kosuke Kitajima put Japan slightly ahead going against Hansen in the breaststroke. Not to worry, not with Phelps going next.
He surged through the water in the fly, handing off a lead of about a quarter of a second to Adrian for the freesytle anchor. The Americans won going away in 3 minutes, 29.35 seconds, just off their own Olympic record from Beijing. Japan held on for silver in 3:31.26, with Australia taking the bronze in 3:31.68.
The U.S. men had never lost the medley relay at the Olympics, and they weren't about to now on the final night of swimming at the Olympic Aquatics Centre, on the final night for such a momentous athlete.
How momentous? The governing body of swimming, FINA, broke with Olympic protocol to present Phelps with an award recognizing his entire body of work. While a video montage played on the board, he made one more victory lap around the pool, even stopping off again at the medal podium he spent so much time on during the Olympics.
"Wow," he said. "I couldn't ask to finish on a better note."
Phelps kept a journal during his last Olympics. He was asked what he would write in it on this day.
"I could probably sum it up in a couple words -- I did it," he said. "I haven't written too much this week. I'm kind of taking everything in."
One of the moments he'll remember: All the swimmers from the other relay teams lining up to shake his hand behind the blocks once he was done.
"It's kind of cool," Phelps said. "The best part of the Olympics is you have people coming from all over the world competing in the best sporting event ever. That's just something you don't see every day."
We may never see the likes of Phelps again.
Of course, he was peppered with questions about a possible comeback, in a year when Ian Thorpe and Janet Evans both failed in their attempts to make it back to the Olympics after long layoffs.
"I don't think so," Bowman said. "We've had a great end to a great run and there's not much more he can do. I guess if he finds after a few years he's searching for something and thinks he can find it in swimming, he could look at it. But I don't think he will. I think he's ready to explore other things. He's done all he can do here."
This night was all about a fitting farewell for Phelps.
He and his relay mates unfurled a banner that said, "Thank You London."
The crowd said thank you right back, chanting "Michael! Michael! Michael!"
Later, as Phelps was getting up to leave one news conference and hustle off to another one, the other three American swimmers were asked if they thought he would really stay retired.
Phelps wouldn't even let them answer, saying very emphatically, "Yes! Yes!"
"I'm sure he's going to be around," Grevers said, "but not in the pool where we like him best."
Information from The Associated Press was used in this report.