American swimmers Michael Phelps and Ryan Lochte set up a last tantalising clash before Phelps retires after the Olympic Games when they qualified for the 200 metres individual medley on Thursday.
Phelps, who won the 200 medley at Athens in 2004 and Beijing four years later, is bidding to become the first man to win the same individual event at three Olympics.
He beat Lochte at the US trials, but finished second behind him in the semi-finals and third overall on Wednesday, although both will go much faster in the final.
Lochte was fastest overall in 1 minute 56.13 despite conserving his energy because he swam the 200 backstroke semi-finals just before the medley.
