Boki’s winning time in his morning heat of the S13 50 metres backstroke was 26.36 seconds, and he lowered that time in the evening’s final as he won in 26.21, finishing ahead of Britain’s Stephen Clegg and Diego Diaz of Mexico.

The World Series features multi-class races, with winners decided by a standardised points system.

The men’s 100m freestyle A Final in the open class produced two gold medallists as Izlam Aslanov of Uzbekistan and The Netherlands’ Michiel Jorink both earned 901 points.

Aslanov produced the faster time, 51.98 seconds, an Area Record, with the Dutchman clocking 54.94.

The women’s 100m freestyle open class saw Liesette Bruinsma, from the S11 category, win in a world record of 01min 05.81sec for 1065 points, ahead of Italy’s Carlotta Gilli, who scored 891, one more than Canada’s bronze medallist Aurelie Rivard, who had broken the S10 200m freestyle record the day before.

Two world records were set in the women´s 50m backstroke as Britain´s Hannah Russell, in the S12 category, clocked 31,61 and Canada´s Shelby Newkirk, in the S7 class, touched in at 38.00.

Two more world records arrived in the men´s 800m freestyle as Uzbekistan´s Dmitriy Horlin, in the S12 class, clocked 8:38.56 and Japan´s Uchu Tomita, S11, set a time of 9:36.61.

The women’s 800m also produced a world record from Mckenzie Coan of the United States, an S7 swimmer, who clocked 10min 37.70sec in winning gold.