BARCELONA, Spain (CBS/AP) -- Missy Franklin climbed to the top of the podium one more time in Spain before heading off to college.
With that step, the 18-year-old joined a very exclusive club.
Missy, we'd like to introduce you to Michael Phelps, Mark Spitz, Ian Thorpe and Kristin Otto.
''I still can't really believe that it happened,'' Franklin said.
She claimed her record sixth gold medal of the world championships Sunday night, swimming the leadoff leg for the Americans in the 400-meter medley relay. Franklin gave the U.S. a slight lead in the backstroke, and her teammates - Jessica Hardy, Dana Vollmer and Megan Romano - made it look easy from there.
The winning time was 3 minutes, 53.23 seconds, nearly two seconds ahead of runner-up Australia, with Russia claiming the bronze.
''I had some really great races that I'm really proud of, and there's still a bunch where I have a lot of room to improve,'' Franklin said. ''So I'm really excited for the next year and the year after that and all the years following those.''
It might be hard to top this one.
Franklin became the winningest female swimmer ever at a world meet, eclipsing the record that was shared by Tracy Caulkins, who won five times in 1978, and Libby Trickett, who did it in 2007.
Perhaps more impressively, Franklin became only the fifth swimmer to capture as many as six golds at either worlds or an Olympics.
Quite a club it is.
Phelps won six golds at the 2004 Athens Olympics, seven at the 2007 worlds and, of course, a record eight at the Beijing Olympics, eclipsing Spitz's mark of seven at the 1972 Munich Games. Otto won six golds at the 1988 Seoul Olympics - an accomplishment since clouded by revelations of rampant doping in East Germany - and Thorpe claimed a half-dozen victories at the 2001 worlds.
Now, there's Franklin.
She completed a grueling week in which she competed in eight events. She dropped out of the 50 backstroke after swimming in the preliminaries of the non-OIympic event, wanting to focus on more important races, and took fourth in the 100 freestyle. Otherwise, it was all gold.
She improved on her performance at the London Olympics, where she was one of the biggest stars with four golds and a bronze.
''I just wanted to see where I was after London,'' Franklin said. ''It's kind of an unknown year. There are so many things that can happen.''
Indeed. Check out what transpired with the American men in their 400 medley relay.
They celebrated what looked to be an easy victory, only to discover that 19-year-old breaststroker Kevin Cordes, the least experienced member of the foursome, left too soon on the exchange between the first and second legs.
The U.S., which touched nearly 1 1/2 seconds ahead of France, was disqualified. The French moved up to take the gold, while the silver went to Australia and Japan snatched the bronze.
''That's like a punch in the gut right there,'' said Bob Bowman, coach of the U.S. men's team.
Cordes stood on the deck in disbelief, hands on his head, but the replay showed he clearly left the block before backstroker Matt Grevers touched the pad. Ryan Lochte could only shake his head, having contributed a strong butterfly leg that didn't matter. He was denied his fourth gold medal of the meet, leaving him tied with Chinese star Sun Yang as the winningest male swimmers.
''A relay disqualification is not a particular individual's fault,'' said Nathan Adrian, who swam the anchor leg in vain. ''It falls on all of our shoulders.''
Franklin was not even chosen as the top female swimmer of the meet. That award went to fellow American Katie Ledecky, who won four golds and set two world records.
She edged out Franklin based on a formula that doesn't count the relays and gives bonus points for world marks.
Franklin had no complaints.
''It could not go to a better person,'' Franklin said. ''I am sooooooo proud of Katie. She was absolutely unbelievable. I think she has probably been my absolute favorite swimmer to watch ever.''
Sun was honored as the top male swimmer after sweeping the freestyle distance events. He closed with a victory in the 1,500, adding to his titles in the 400 and 800. After dueling with Canada's Ryan Cochrane most of the way, the Chinese star turned it on the last two laps and won going away in 14:41.15.
Cochrane took silver and Italy's Gregorio Paltrinieri bronze. Americans Connor Jaeger and Michael McBroom finished off the podium in fourth and fifth.
''I really appreciated (that) my opponent pushed, otherwise I wouldn't have been able to make it,'' Sun said through a translator. ''After all my races I felt a bit fatigued. But I just tried to convince myself to stay with him, because I knew that in the last 100 I had the advantage.''
Sun's week also included the fastest leg by far on the 800 free relay, which almost singlehandedly give China a bronze medal in that event.
In other events on the final night at the Palau Sant Jordi, Japan's Daiya Seto held off American Chase Kalisz to end U.S. domination of the men's 400 individual medley, Hungary's Katinka Hosszu won the women's 400 I.M., and Ranomi Kromowidjojo of the Netherlands took the women's 50 freestyle.
Seto touched in 4:08.69 to take gold in a race that had been won by U.S. stars Lochte and Michael Phelps at every major meet since the 2005 worlds in Montreal.
Phelps is retired - for now - and Lochte has dropped the grueling race, at least for this season.
The 19-year-old Kalisz, who trains at Phelps' club in Baltimore, was far back after the butterfly and backstroke legs. But he began to close on the breaststroke and nearly caught Seto on a freestyle dash to the finish. He settled for silver, with the bronze to Brazil's Thiago Pereira. American Tyler Clary was fourth after taking the silver behind Lochte at the 2011 worlds.
Hosszu was more than 2 seconds under world-record pace through the first three legs, giving her a big enough lead to hold on in the freestyle. She touched in 4:30.41, while Spain's Mireia Belmonte thrilled the home crowd by taking silver. Elizabeth Beisel of the United States earned the bronze, just ahead of hard-charging teammate Madeline Dirado.
Kromowidjojo's victory was a reversal of the 100 free, which was won by Australia's Cate Campbell with the Dutch sprinter taking the bronze. Campbell took silver this time, just 0.09 behind the winner's time of 24.05. Francesca Halsall grabbed the bronze, Britain's only medal of a hugely disappointing meet.
The U.S. had a grand ol' time, finishing atop the swimming medals table with 13 golds and 29 overall - matching its total haul at the 2011 worlds in Shanghai.
In non-Olympic events, Yuliya Efimova won the women's 50 breaststroke in 29.52, edging world-record holder Ruta Meilutyte of Lithuania, while Hardy took the bronze. Camille Lacourt of France won the men's 50 backstroke with a time of 24.42. Grevers tied for the silver with another Frenchman, Jeremy Stravius.
Franklin saved the best for last.
Now, she's off to college at Cal in a few weeks.
''I can't wait,'' Franklin said. ''It just feels more real every second, and I can't wait for the experience.''
This one wasn't too shabby, either.
(Copyright 2013 by CBS San Francisco. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed)
for more features.