Katie Ledecky, inside 1:57 for the first time over 200m and on 4:05 over 400m, concluded her Mesa Grand Prix test with a season world-leading 8:20.64 in the 800m that confirmed what opponents already knew: the 16-year-old Olympic champion has been working on her intention to add world titles to her young treasury this summer in Barcelona.

At London 2012, she thumped the best of the rest with a sizzling pace from go to gold in 8:14.63. She was just 15 and had stepped up from an 8:37 best at 14. Under the guidance of coach Yuri Suguiyama at Nation's Capital Swim Club (formerly the Curl Burke Swim Club before scandal intervened), Ledecky is on a roll. 

Mid-season 4:05 and 8:20 is somewhat beyond anything she has done at this stage before - so where will she be come trials, where when the heat is on in the Catalan capital when focus turns to the FINA showcase from July 19 to August 4? This evening in Mesa, next home was Chloe Sutton, on 8:36.81, Andreina Pinto on 8:41.54, both efforts a pool apart from what unfolded at the helm of the race.

Just where swimmers are on the spectrum own preparation for bigger moments is best known to those steeped in the stuff of training cycles and timing of events. While there was plenty of class on show in Mesa, nothing came close to the  quality on the clock produced by Ledecky. 

Cammile Adams took the 200m butterfly in 2:09.45, ahead of the busiest swimmers at the meet, Hungarian world cup winner Katinka Hosszu, 2:10.24, Kathryn McLaughlin third in 2:12.93.

Hosszu was far from done. Olympic champion Missy Franklin took the 100m backstroke in 1:00.15 ahead of Rachel Bootsma, 19, on 1:00.54, and Elizabeth Pelton, 19, on 1:00.84, Hosszu in the fray on 1:03 after a 1:01.74 heat. 

The Hungarian then kept the rest at bay in the 200m medley, on 2:12.68, ahead of Sweden's Stina Gardell,2:13.81, and Cal's Caitlin Leverenz, 2:13.90.

Tyler Clary swam heats of the 200m butterfly and 200m medley but the prospect of too much pain saw him drop the four-stroke challenge for finals, the 'fly race his in 1:58.10 ahead of Joseph Schooling, 17, on 1:58.83, and Bobby Bollier, 1:59.80.

Breeja Larson, the breaststroke bolter from US trials last year, laid down a solid 1:07.32 marker in the 100m  ahead of Jamaica's Alia Atkinson, 1:08.41, and Sweden's Rebecca Ejdervik, 1:09.28. 

Mike Alexandrov took the 100m breaststroke in 1:00.63 ahead of Eatu Karvonen, seeking Finnish selection for Barcelona in 1:01.97,  with Bernard Johnson and Mark Gangloff next home in 1:02.68 and 1:02.72.

Olympic champion Matt Grevers pipped David Plummer 54.26 to 54.28 in the 100m backstroke, Eugene Godsoe and Ryan Murphy, 17, next home in 54.77 and 54.81 respectively.

In the 200m medley, South African Darian Townsend inflicted a 2:01.04 defeat on Olympic silver medallist Ryan Lochte, on 2:01.90, Zac Dalby on 2:04.72 for third. The 1500m free went to Michael Klueh in 15:28.57, the 30-lap men on times that more than most reflect work aimed at other moments.