Atkinson took the shine off the Katinka Hosszu (HUN) caravan by swimming the second fastest 50m breaststroke of the year and bettering her personal best for a score of 985 points.
However, Hosszu was the most medalled woman with five golds and two silvers, only missing the podium in one race — the 50m butterfly — in her final event.
Le Clos opened his medal haul with a 200m freestyle victory, using lane three to head off Australian Thomas Fraser-Holmes in lane seven. Le Clos touched in 1:42.29 in a race that had early splits close to world-record time. Fraser-Holmes and Le Clos jumped at the same time, leaving early leaders Regan Leong (AUS) and Myles Brown (RSA) out of the placings, but having done their job of taking the finalists out at a fast clip. Third-placed Robert Hurley (AUS), who swam 1:43.44, won this event in Dubai.
"Last night was probably the best night I’ve had in short course, while tonight was more about racing against good competitors to see where I’m at. I hope to take part in the freestyle events in 2016 (Olympics) and will train to be the best in that in addition to the butterfly. At the end of the day when I hang up my swimming goggles, I want to know that I did my best in everything," said Chad Le Clos.
Le Clos withstood a spirited challenge from Konrad Czerniak (POL) in lane two to win the 100m butterfly — his fourth series win — touching in 50.04, five hundredths clear of Czerniak and Australian Tommaso D’Orsogna (50.86).
There was no doubt about adding a fifth gold in the 200m IM, finishing in 1:53.36 over Fraser-Holmes — who claimed a gold and three silvers from the meet — and Brazilian Henrique Rodrigues. It was Le Clos’ fourth win in the event this year.
Atkinson gained an edge over Barcelona world champion Iuliia Efimova (RUS), winning the 50m breaststroke in 28.94, just 0.14 outside Jessica Hardy’s world mark set in 2009. Both swimmers went into the race with two wins apiece this year. It improved her personal best of 29.21 set in Berlin and gave her top points in Singapore. She also won gold in the 100m breaststroke on the first night and a bronze in the 100m IM tonight.
"This is the first time I’m competing in every single meet in the series. I always hope to improve my timing from the first to the third leg in each cluster, so I’m very happy with the timings I’ve clocked in this first leg and hope to continue improving at Tokyo and then Beijing. I’m a big fan of the Asian cluster and I’ll definitely want to be back, especially in Singapore and Japan - the atmosphere makes it a great place to be," said Atkinson.
Hosszu’s opening swim of the night, the 400m IM, registered 4:27.60, and was nearly seven seconds off her Berlin world-record pace. She seemed to tire over the freestyle leg as Britain’s Hannah Miley (4:28.75) and Spain’s Mireia Belmonte (4:28.90) hunted her down. However, it was good enough for a sixth straight 400m IM victory.
"It wasn’t my goal and I’m not disappointed that I didn’t break any records during this time in Singapore. After all, I did take part in 11 events and it would have been surprising if I did break a record! I'm very happy about leading this leg and I feel great moving on to the others," said Hosszu.
She won the 100m backstroke over Australia’s Emily Seebohm, was out-touched for gold by German Franziska Hentke in the 200m butterfly after winning the previous five editions, and had a rapid start to the 50m butterfly, but fatigue set in and she finished last.
In the splash-for-cash 50m freestyle, Vladimir Morozov gained his fifth win of the series with a decisive victory in 20.78 over George Bovell (TRI) and Anthony Ervin (USA). He was first off the blocks and never looked threatened, even with fourth-placed world record holder Roland Schoeman (RSA) on his shoulder.
"It feels good to win. I always aim and hope to win, but I admit that I’m not very happy with the time I’ve clocked. I think it is the slowest I’ve got this World Cup," said Morozov.
The other United States swimmer, Eugene Godsoe, took a clean sweep of the men’s backstroke events, with the 50m and 200m races tonight.
Such was the strength of the 100m men’s breaststroke field that Barcelona world champion Christian Sprenger (AUS) missed the cut, only notching the ninth best time — a big come-down from the previous day when he was involved in both mixed relay world records. Gold went to Hungary’s Gergely Gyurta, ahead of Morozov and Brazil’s Felipe Lima. Morozov also collected three gold medals in Singapore.
Australian Cate Campbell, 100m freestyle champion in Barcelona, held out a fast-finishing Moscow winner, Sarah Sjoestrom, winning in a smart 51.67. Sjoestrom denied Emma McKeon (AUS) the silver by 0.07.
New Zealand’s sole representative, Lauren Boyle, completed the 400m-800m freestyle double when beating Moscow, Doha and Dubai winner Melanie Costa (ESP) and her team-mate, world record holder Mireia Belmonte.
South African Myles Brown claimed his third 1500m freestyle gold medal of the series with a 14:56.94 win over Gyurta (14:58.43) by jumping out of Gyurta’s shadow at the 1400m.
In the 4x50m mixed freestyle relay, Brazil shook France’s world record with a speedy 1:31.20, just six one hundredths shy.
THE BEST PERFORMERS IN SINGAPORE
1. LE CLOS Chad (RSA): 1:48.56 - 1015 pts - 200m fly
2. MOROZOV Vladimir (RUS): 51.36 - 962 pts - 100m IM
3. GYURTA Daniel (HUN): 2:02.62 - 953 pts - 200m breast
1. ATKINSON Alia (JAM): 28.94 - 985 pts - 50m breast
2. HOSSZU Katinka (HUN): 2:05.33 - 982 pts - 200m IM
3. COUTTS Alicia (AUS): 58.32 - 970 pts - 100 IM
PROVISIONAL LEADERS OF THE OVERALL RANKING (after Singapore)
1. LE CLOS Chad (RSA) - 436 points
2. MOROZOV Vladimir (RUS) - 303 points
3. HURLEY Robert (AUS) - 216 points
1. HOSSZU Katinka (HUN) - 675 points
2. ATKINSON Alia (JAM) - 228 points
3. BELMONTE Mireia (ESP) - 214 points