US Olympic swimmer Michael Phelps poses with his Special Laureus Award during the 2013 Laureus World Sports Awards, at Municipal Theater in Rio de Janeiro March 11, 2013. [Photo/Agencies]

VANCOUVER - US Olympic swimming star Ryan Lochte said Wednesday he has no doubt superstar Michael Phelps will end his retirement and return to the pool for another shot at Olympic glory at the 2016 Rio Games.

Speaking in Vancouver where he is swimming in a local meet in the Canadian city this weekend, the 28-year-old Lochte, winner of 11 Olympic medals and holder of three world records in the individual medley, told a media scrum it' s not a question of if the 27-year-old Phelps will return but when.

"Michael  Phelps is the hardest racer I' ve ever went up against, and what he' s done for this sport of swimming is tremendous," he said.  "I hope he comes back in. I think he will. I know he will. It' s just a matter of time and when. I know he will."

Lochte wouldn' t say if he had talked to the winner of a record 22 Olympic medals who announced his retirement last year following the London Olympic Games.

"I  can' t say. I just have a feeling. I' ll just leave it at that. I have a feeling he' ll come back," he said, adding the sport would be better with Phelps return.

"Racing  him (Phelps) was one of the biggest challenges in my swimming career and I loved it. I' ve gotten to the point where it was one of his biggest challenges too and just the friendship that we' ve developed throughout the years of racing each other and the rivalry it' s one of the biggest in the sport and we had a lot of fun doing it. So I definitely hope he comes back because in a way he pushed me and I pushed him. So it was definitely great for the sport.

Lochte, who has cashed in on his Olympic notoriety with his own reality TV show and millions of dollars in product endorsements, is currently back in the pool after a prolonged break following last summer' s Olympics.

With a month of serious training under his belt, he is gearing up for the final US grand prix event of the year next week in Santa Clara, California, with a goal of qualifying for the World Championships in Barcelona, Spain, starting July 19.

Lochte, who won five gold medals and a bronze at the 2011 Worlds in Shanghai, said he wanted to be in Spain and it was now just a matter of qualifying.

"I definitely would be upset (not to go to Spain), I mean that' s what I' m training for. I' m training to go to world championships and medal in each event that I go to, but I' m taking whatever I can this year just because my training has not been there. I mean I really haven' t been training the way I used to, so this year is definitely trial and error. We' ll see what happens."

Despite his erratic schedule of being both a celebrity and a world-class swimmer, Lochte said his long-term goal was to compete in the Rio Olympics when he will turn 32 during the Games.

He didn' t feel his age would be an issue and cited Dara Torres as an example. The US swimmer won three silver medals at the 2008 Beijing Olympics at 41-years-old.

"So I don' t think age has anything to do with it. I think it is how you prepare yourself and as you get older, I mean you still have to put in that work, and coach (Gregg) Troy, my coach, is one of the world' s greatest coaches and he knows how to coach me and you know, I' ll just listen to him and go from there and we' ll see what happens."