“A final spot is a final spot,” said Phelps, whose 14 Olympic gold medals include the record-setting eight he won in Beijing four years ago.
Slated to swim seven events in London, Phelps has acknowledged that the world has closed in on him, and his chances of gaining gold in each are slim.
A chief stumbling block is his own US team-mate Ryan Lochte, who clocked the third-fastest time of the morning behind Japan’s Kosuke Hagino and South African Chad le Clos.
Hagino uncorked a Japanese record of 4min 10.01sec to win the third of five heats.
Phelps won the fourth heat in a leisurely 4:13.33. Laszlo Cseh was second, but the Hungarian’s time of 4:13.40 left him out of the final with the ninth-fastest time and unable to try to add to the silver medal he won in Beijing and bronze from Athens.
Lochte looked happy to settle for second in the fifth heat behind le Clos, slowing visibly at the end after leading most of the way.
“I’m glad I got the cobwebs out,” Lochte said. “All I had to do was get a lane for tonight, so I’m very happy.”
It’s not unsusual for top swimmers to keep something in reserve for the final of the 400m medley, the punishing event that Phelps swore he’d never race again when he climbed out of the pool after winning in Beijing.
Phelps admitted that he might have made a miscalculation. His lowly finish mean’s he’ll start in an outside lane on Saturday night, rather than in a more favorable center lane.
“I didn’t expect those guys to go that fast,” Phelps admitted. “I just wanted to try to get some good underwater, try to get some good times.
“You can’t win the gold medal from the morning,” he added philosophically.
Lochte, who won the long medley world title in Shanghai last year as Phelps sat out, edged Phelps at the US trials last month, where his first-ever win over his compatriot in the event whetted appetites for their Olympic showdown.
Lochte clearly remained wary of his old foe.
“It’s a tough field but he’s in, so you can’t count him out, even though he just squeaked in in eighth place,” Lochte said.
“He’s a racer and we’re going to do everything we can to go one-two tonight.”
Hagino, who had topped the world rankings for 2012 until Lochte and Phelps moved past him at the US trials in Omaha, planned to have something to say about that.
“There are a few things I want to improve on in the afternoon,” he said. “I can definitely improve in the last quarter of the race.”