Michael Phelps of the US walks out to swim the men's 100 meters freestyle heats during day two of the 2014 Pan Pacific Championships in Gold Coast, Australia on Friday. Photo: AFP

It was just like old times for Michael Phelps on Friday. The world's most-decorated swimmer was on the top of the podium at the Pan Pacific Championships, collecting another gold medal after a thrilling race win.

He had just helped the Americans win the 4x200 meters freestyle relay after a titanic struggle against Japan at Australia's Gold Coast on a rainy ­winter's night.

For a man who has won a mind-­boggling 18 Olympic gold medals, it might normally have seemed like just another day at the office, but not this time. The importance was not lost on Phelps, who was swimming at his first international meet in two years in an event the Americans have not lost for over a decade.

"I think being able to hold that tradition for this long and being able to get back on the podium, it feels amazing," Phelps told reporters.

Comebacks have invariably been cruel to swimmers and even Phelps has struggled to get near his best but Friday was a good day for the 28-year-old.

Not only did he win a relay gold but he also finished an impressive fourth in the 100 meters freestyle final despite taking on the world's best sprinters in an event he rarely ­competed in, even at his peak.

His time of 48.51 was exactly one second outside his best-ever time for the blue-riband sprint but was the best sign yet that he is on track to make a big splash at the 2016 Rio Olympic Games.

The final was won by Australia's Cameron McEvoy in 47.82. Behind him was the reigning Olympic champion Nathan Adrian (48.30) and the two-time world champion James Magnussen (48.36).

Swimming's new teen queen Katie Ledecky collected her third title in two days of competition by helping the US win the women's 4x200 meters freestyle relay.

The 17-year-old holds the world ­records for 400, 800 and 1500 ­meters but is starting to experiment with ­shorter events. She won the 800 and 200 ­meters on Thursday. And although she found the 100 meters too short for her liking, finishing 13th overall in Friday morning's heats, she overcame a one-second deficit on the anchor leg to win the relay.

Missy Franklin, still battling the ­effects of back spasms, also picked up gold in the relay after a disappointing start to the four-day meet.

The Colorado teenager failed to qualify for Thursday's 200 meters freestyle final and finished third in the 100 meters backstroke, two of the events she won at last year's world championships, and finished fourth in the 100 meters freestyle final.