Michael Phelps 'frustrated' by current form after Arena Pro Swim Series failure

USA Olympic swimmer Michael Phelps has admitted that he is 'frustrated' by his current form after failing to win at the Arena Pro Swim Series in Charlotte, North Carolina at the weekend.

The 29-year-old aimed to take on compatriot Ryan Lochte in the pool, but he failed to make the final in the 200m individual medley and the 100m freestyle races.

"It's just frustrating not setting myself up like I should have," Phelps told reporters. "What I want most is to be racing the competition I need to be racing. I want to race Ryan and those guys. It's frustrating falling short."

Phelps, who recently served a six-month suspension after being convicted of drink-driving, is the most decorated Olympian of all time with 22 medals.