LONDON (AP) — A little payback. Another shiny new medal to add to a collection that isn't quite complete even yet.

It seems kind of silly to say Michael Phelps needed to win the gold medal Thursday night in his second Olympic showdown with rival Ryan Lochte — not when he already had 15 of them stashed away somewhere for safekeeping.

His place in Olympic history was secure before he even tested the water in the London pool. And all he did this week was add another mark to the record books by becoming the biggest medal winner ever in any Olympic sport.

But need it he did, which might explain the smile of satisfaction on his face after holding Lochte off in his final kick in the 200-meter individual medley for his first individual gold in London. In the last race of his career against Lochte, he not only came out a winner but set himself up nicely for what will likely be two more gold medals before his last Olympics is finally over.

"It's a relief to win an individual gold," Phelps admitted afterward. "I fell short in the first couple of events."

The frustration Phelps felt in being edged out for the gold on his last stroke in the 200 butterfly was forgotten, at least for the night. So was the lopsided loss to Lochte in their first meeting in the 400 IM here, where Phelps looked so ordinary that the whispers began that he might be finished.

He's not, and odds are he's not done adding medals to his record haul either.

Two more races, two more good shots at gold. By the time he finishes on Saturday, his tally will be complete — and it will be staggering.

Forget the talk about him being the greatest Olympian ever, better than Jesse Owens or Larissa Latynina, the Soviet gymnast who until this week held the record for most medals ever. There isn't such a thing, anyway, because a swimmer has nothing in common with an boxer, just as a basketball player has nothing in common with an archer.

But we may never see an athlete dominate for so long the way Phelps has dominated swimming the last three Olympics. Six golds in Athens and eight in Beijing will make this Olympics pale by comparison, but Phelps will still almost surely leave London as the biggest medalist of these games.

"Phelps is out of our league," Serbia's Milorad Cavic said.

He sure looked that way again on this night, touching at 1 minute, 54.27 seconds, just off his winning time in Beijing, to become the first male swimmer to win the same individual race in three consecutive Olympics. It was in marked contrast to the stumbling start he had five days earlier when Lochte beat him by 4 seconds in the 400 IM and Phelps didn't win any medal at all.

Then came the the loss in the butterfly to Chad le Clos of South Africa when he tried to glide in instead of taking an extra stroke. The whispers became even stronger that either Phelps didn't train hard enough for these games or that there was something wrong with him.

Wrong on both counts.

Lochte had come into London hoping to take Phelps down, and be the biggest medal winner himself. He's done here, but not before having an Olympics most athletes can only imagine — two golds and five medals overall — beating Phelps head-to-head for one of them.

In the ready room before their race, the two friends and rivals laughed and joked with each other, both knowing their days of racing each other were about over.

"We've been racing for eight years now and the rivalry we created has been tremendous for the sport and our friendship," Lochte said. "I'm going to miss him."

A lot of people are going to miss Phelps — including NBC, which rode his gold medals to big ratings every time he got in the pool. Indeed, his legacy may not just be in the medal count but the star power he gave his sport and the way he helped keep the U.S. dominant in Olympic swimming.

He's got two races left, a 100-butterfly on Friday and a 4x100 medley relay Saturday that will officially end his remarkable career. He warmed up for the butterfly with a dominating performance in the semifinal after his gold medal race and will be a heavy favorite to win his last individual gold.

It's entirely conceivable — no, make that likely — that Phelps will go home with four golds and two silvers in seven races here. That's not the eight golds of Beijing, but it will make him the biggest medal winner among swimmers and would bring his final Olympic medal total to 22, 18 of them gold.

Their rivalry is over, and his Olympics is about over.

And with it, one of the most brilliant careers in sports will be over.