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 4×100-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."

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 wasn’t the only star of the night. Missy Franklin capped off a brilliant Olympic debut by helping the U.S. take gold in the women’s 400 medley relay — with a world-record time, no less.

The 17-year-old Franklin, who will begin her senior year of high school when she gets back to Colorado, seems destined to be America’s new star in the post-Phelps era after taking four golds, tying Amy Van Dyken at the 1996 Atlanta Games for the most by a U.S. female swimmer. The youngster also picked up a bronze while swimming seven events — the same number as Phelps.

"I don’t think his shoes will ever be filled. They’re so huge," Franklin said. "Hopefully I can make little paths next to him."

And let’s not forget Allison Schmitt, another swimmer with ties to Phelps. They trained together over the past year in Baltimore, becoming fast friends with all their goofy antics. But they sure took care of business in the pool, with Schmitt winning three golds, a silver and a bronze in London.

The Americans dominated the medal count at the pool, finishing with 16 golds and 30 medals overall.