LONDON — As Michael Phelps finished the last lap of his last training session before his last night of Olympic swimming, Bob Bowman, his longtime coach, started feeling the emotion swell. He later said he felt uncomfortable and weird.

And then Phelps, his historic career hours from concluding, poked his head out of the water and summoned his coach of 16 years to the side of the pool.

"I've been able to become the best swimmer of all time," Phelps told Bowman, he recalled later. "I said, 'We got here together.' I thanked him."

That's when Bowman lost it, spilling tears that would leave his eyes reddened throughout the last night of the Olympic swimming competition, which would feature Phelps' final act: a gold medal as part of the U.S. 4x100 medley relay team that included Bremerton's Nathan Adrian swimming the freestyle leg.

"My tears I can hide behind my goggles," Phelps said to his weeping coach. "Yours are streaming down your face."

It was a night of tears, reflection and joy as one era ended and another bloomed. Phelps' final victory came immediately after the U.S. women's squad, featuring 17-year-old Missy Franklin, went under the world record in the 4x100 medley relay, winning the gold in 3 minutes, 52.05 seconds. With Phelps swimming the butterfly leg and Adrian extending the lead on the last leg, the men touched home in 3:29.35.

As Phelps wrapped up his career with 22 Olympic medals, the meet unveiled his apparent female heir. "It is unreal," Franklin said, adding later, "I don't think his footsteps will ever be filled."

Both she and Phelps, who has spent his entire career at the North Baltimore Aquatic Club, collected four gold medals here, winning two individual events and two relays; she added a bronze in the 4x200 individual medley relay, he got a silver in the 4x100 freestyle relay and 200 butterfly.

It was hard to tell who had more fun. Franklin, who won the 100 and 200 backstroke events while setting a world record in the 200, seized the stage with nightly displays of fearlessness and joy.

"Being here in this type of experience with the most incredible teammates you could ask for around me, it's absolutely impossible to get grumpy," she said Friday.

Phelps, 27, got handshakes from many of his opponents and hugs from his teammates. He said he will not be back for the 2016 Games in Rio de Janeiro because he doesn't want to be competing at age 31. He swam in his first Olympics at age 15 in 2000, finishing fifth in the 200 fly. He won six gold medals and two bronzes in Athens in 2004. He won eight gold medals at the 2008 Games in Beijing.

Phelps didn't have the most impressive night Saturday — that distinction belonged to China's Sun Yang, who obliterated his world record in winning the 1,500 freestyle in 14:31.02 — but he got the biggest party.

At the end of the night, the end of his career, Phelps received an unexpected surprise: a silver trophy from the world swimming governing body (FINA). The crowd showered him with appreciation, and Bowman did a bit more crying.

"We've had a great end to a great run," Bowman said.