Phelps fastest in comeback

Michael Phelps returned to competitive swimming with the quickest time in qualifying for the men's 100 metre butterfly in Arizona.

The 28-year-old has not raced since the London 2012 Games, but lay down the marker for United States rival Ryan Lochte with a time of 52.84 seconds - in the 14th and final heat - to ease into the final at the Arena Grand Prix in Mesa, Arizona later in the day.

Five-time Olympic gold medallist Lochte was the second fastest qualifier in 52.94secs.

Phelps has won 22 Olympic medals, including 18 golds, and also holds the world and American national record for the 100m butterfly.