Ryan Lochte swims in his men's 200m individual medley semifinal during the U.S. Olympic swimming trials. (JEFF HAYNES/REUTERS)

There were six other men in the first semifinal of the 200-meter individual medley Friday night at the U.S. Olympic team trials in swimming, but it was very difficult to notice them as Ryan Lochte and Michael Phelps, swimming side by side and nearly stroke for stroke, once again turned an eight-man race into a two-person duel.

This race that really didn’t matter all that much clearly mattered a lot, providing a warm-up for a huge Saturday night of competition for both men.

With each holding a victory from their first two head-to-head races, Saturday’s 200 medley final likely will determine the U.S. team’s biggest male star entering the London Games. Based on his performance Friday, Lochte enters with the psychological edge.

“I had to do what I had to do to get my hand on the wall first and get a spot in the final” Saturday, Lochte said. “I’m definitely pleased with how I swam.”

Despite competing in the 200 backstroke semifinals earlier in the night, Lochte outmuscled Phelps over the last two laps of the 200 medley, winning by 1.05 seconds with his victory in 1 minute 55.51 seconds. The strong performance despite the demanding double made it clear he intends to retain his supremacy in an event Phelps once owned.

“Obviously, I want every race,” said Phelps, who turns 27 Saturday. “Hopefully, I’ll get a birthday present.”

Lochte might have, at least, a little surprise for Phelps on Saturday: His coach, Gregg Troy, said Lochte was considering swimming in the 100 butterfly heats that morning. If Lochte were to pursue that event, that could mean one last — and unexpected — encounter between Phelps and Lochte in an event final.

“He’s going to swim the butterfly tomorrow morning,” Troy said. “We’ll decide where to go from there.”

No other birthday gift would come willingly from Lochte, who has won the last two world titles in the event and led all qualifiers Friday night. Phelps, who has won the last two Olympic 200 medley gold medals, touched the wall in 1:56.66. The next best finisher, Conor Dwyer, came home in 1:58.32.

“I knew he kinda took off,” Phelps said about the second half of the race. “I was like, ‘Oh, I probably should save something for [Saturday]. I kind of just shut it down. The race was kind of over.”

More than an hour before, Lochte easily posted the fastest time in the 200 backstroke semifinals, touching the wall in 1:55.73.

“It seems every time I do those doubles, it gets shorter and shorter resting,” he said. “I think tomorrow I’ll only have about 15-20 minutes. . . . You know what? I’m up to the challenge.”

If testosterone flowed during the 200 medley semis, speed and sentiment dominated the men’s 100 freestyle final. As Nathan Adrian claimed the 100 freestyle title in 48.10, topping Cullen Jones, who touched the wall in 48.46, Jason Lezak came home in 48.88, good enough for sixth place.

Lezak, 36, had clinched a place in his fourth Olympic Games by the narrowest of margins. A day after getting bumped into the final after Lochte scratched from the event, Lezak earned the last 4x100 relay team slot for London. When he saw the result, Lezak leaned his head against the pool wall in relief.

At the 2008 Summer Games, Lezak almost single-handedly salvaged Phelps’s quest for eight gold medals by chasing down a favored French swimmer with the fastest relay leg in Olympic history.

“I was nervous, no doubt about it,” Lezak said. “It was a big race for me. I trained four years for this; it’s been real hard. Nobody really understands how hard it’s been for me except my wife and I. . . . It’s a great feeling. I learned a lot. Hopefully, I can be a team leader and help these guys swim fast.”

Lezak’s time Friday bettered his performance in the semifinals by .17 seconds.

“I’m actually really surprised I was able to go faster than last night,” Lezak said. “I felt terrible [Friday]. This 36-year-old body was broken down a little bit.”

In other news, a pair of newcomers clinched Olympic team spots in the 200 breaststroke. Scott Weltz, who finished 37th in this event in 2008, used a furious finish to touch the wall first in 2:09.01, and Clark Burckle, fifth in ’08, got second in 2:09.97. In the women’s 200 fly, Cammile Adams won in 2:06.52, topping Kathleen Hersey, who finished in 2:07.72.

Teresa Crippen, whose brother Fran Crippen drowned during an open-water swimming race in the United Arab Emirates at age 26 in 2010, finished fourth in 2:09.45, missing out on an Olympic team berth.

“It’s hard not to feel that weight every single day,” Crippen said. “I tried to put it behind me for this meet, but it’s a weight I’ll bear for the rest of my life.”

The 200 medley semifinals carried a lighter kind of emotion. Phelps beat Lochte to the first wall by .01, then lost ground on the backstroke leg, reaching the halfway point in 54.66 as Phelps hit the wall in 54.81. Lochte built the lead from there.

“All four strokes are solid,” Troy said. “That time right now . . . could be a little faster.”