The 18-year-old South African claimed two golds on Wednesday night and added a third in the 200m individual medley in Spain.
Sates finished over a body-length ahead of the chasing pack, reaching the finish in 1:58.31 with Switzerland’s Jeremy Desplanches second in 2:00.30 and Italian Alberto Razzetti third in 2:00.41.
Fellow teenager Pieter Coetzé claimed two silver medals on Thursday. He finished second in the 50m backstroke in 24.78 seconds with American Michael Andrew taking gold in 24.64. The Pretoria swimmer then finished second in the 200m backstroke in 1:57.85 with Britain’s Luke Greenbank taking the title in 1:56.88.
Also taking silver on Thursday was budding breaststroker Lara van Niekerk. Having dipped under the 30-second mark with a meeting record at the opening leg of the series in Monaco last weekend, the 19-year-old from Pretoria finished second in the 50m breaststroke in 30.35, with Germany’s Anna Elendt taking gold in 30.10.
Van Niekerk was particularly pleased with the result after missing out on the A final in the 100m breaststroke a day earlier.
Meanwhile, veteran Chad le Clos just missed out on a podium spot in the 200m butterfly. The 30-year-old former Olympic champion led the race early on but ran out of steam to finish fourth in 1:56.38.
Racing continues at the third and final leg of the Mare Nostrum series in Canet, France this weekend, from 28-29 May.