Michael Phelps, the most-decorated Olympian in history, is ending his 20-month retirement to swim in competition later this month, USA Swimming announced on Monday.

The 18-time gold medallist is entered to compete on April 24-26 in Mexa, Arizona, at an event on USA Swimming’s 2013-14 Arena Grand Prix Series.

In Mesa, Phelps plans to enter the 50-and 100-metre freestyles and 100-metre butterfly events, agent Drew Johnson told the Baltimore Sun.

His coach, Bob Bowman, told the Chicago Tribute that Phelps was following a lighter schedule, “doing half the training he used to.” “We have discussed a long-term plan in general terms, but until he swims in a meet we’re not going to know,” Bowman said. “Will he be eighth? Second? Sixteenth? I think he certainly won’t be embarrassed swimming in the meet, and I think he will be competitive.”

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