Swimmer Michael Phelps is coming out of retirement. It could be a first step for him competing in the 2016 Rio Olympic Games.

Phelps, who has won 22 Olympic medals, will compete in the Arena Grand Prix in Mesa, Arizona later this month. He will swim in the 50 and 100-meter freestyles and the 100 butterfly at the competition. The Grand Prix will be Phelps first competition since he competed in the London Olympics in 2012, according to the Baltimore Sun.

"I think he's just going to test the waters a little bit and see how it goes," Bob Bowman, Phelps coach said. "I wouldn't say it's a full-fledged comeback."

Bowman went on to add, "He's gotten back into good shape since September. He can give a good effort and certainly not be embarrassed. He's in enough shape to swim competitively."

Last fall Phelps started training and re-entered the U.S. drug testing program. He is now eligible for competition because he completed the six month wait period that’s required to be eligible. Phelps is the winningest athlete in Olympic history. In the last three Summer games he has won 18 gold medals and 22 medals overall, according to the Associated Press. In Beijing in 2008 he broke Mark Spitz’s record for gold medals at a single Olympics with eight gold medals.

Phelps isn’t the only U.S. swimmer that will be competing in the Arena Grand Prix. Olympians Ryan Lochte and Katie Ledecky will be competing also. Phelps could compete in the U.S. National Championships in August, where the teams for the 2015 world championships will be selected, if his results are good.