| Preliminary Round August 28 - September 1st, 2021
 18 Nations, 4 Groups, the 1st Nations from each Group will qualify for the Quartelfinals, the 2nd and 3rd will qualify for the 1st-12th Places Quartelfinals, the 4th and 5th Nations Nations from each Group will qualfy for the 13th-20th Places Quartelfinals
 
Group A
 Group B Argentina Croatia Italy Russia Uzbekistan 
 Group C Czech Republic Serbia Slovakia Spain United States 
 
 Group D Brazil Egypt 
 Germany 
 Hungary 
  Greece Kazakhstan 
 Montenegro 
 South Africa 
 
 Group ACentral European Summer Time (GMT +2)
Uzbekistan  1 - 38  Russia
Quarter-by-Quarter: 0-10, 0-8, 0-12, 1-8
August 28th 2021, h. 09:00, Swimming Complex Podoli, Prague 
 
Croatia  20 - 7  Argentina
Quarter-by-Quarter: 4-2, 5-1, 6-3, 5-1
August 28th 2021, h. 10:30, Swimming Complex Podoli, Prague Argentina  30 - 7  Uzbekistan
Quarter-by-Quarter: 7-1, 5-1, 10-2, 8-3
August 29th 2021, h. 15:00, Swimming Complex Podoli, Prague 
Italy  12 - 13  Croatia
Quarter-by-Quarter: 2-3, 3-2, 5-2, 2-6
August 29th 2021, h. 16:30, Swimming Complex Podoli, Prague Russia  12 - 5  Argentina Quarter-by-Quarter: 5-0, 3-1, 2-3, 2-1
 August 30th 2021, h. 12:00, Swimming Complex Podoli, Prague
 Uzbekistan  1 - 40  Italy
Quarter-by-Quarter: 0-9, 0-7, 1-13, 0-11
August 30th 2021, h. 13:30, Swimming Complex Podoli, Prague 
Italy  9 - 9  Russia Quarter-by-Quarter: 1-2, 2-4, 4-0, 2-3
 August 31st 2021, h. 12:00, Swimming Complex Podoli, Prague
 Croatia  31 - 1  Uzbekistan
Quarter-by-Quarter: 12-0, 8-0, 5-0, 6-1
August 31st 2021, h. 13:30, Swimming Complex Podoli, Prague 
Russia  5 - 13  Croatia Quarter-by-Quarter: 0-5, 3-2, 0-4, 2-2
 September 1st 2021, h. 09:00, Swimming Complex Podoli, Prague
 
Argentina  8 - 15  Italy
Quarter-by-Quarter: 2-4, 3-2, 1-5, 2-4
September 1st 2021, h. 10:30, Swimming Complex Podoli, Prague 
 Group A Final Standing
| Team | P | W | D | L | GF | GA | +/- | Pt. |  |  Croatia | 4
 | 4
 | 0
 | 0
 | 77
 | 25
 | +52
 | 8
 |  |  Russia | 4
 | 2
 | 1
 | 1
 | 64
 | 28
 | +36
 | 5
 |  |  Italy | 4
 | 2
 | 1
 | 1
 | 76
 | 31
 | +45
 | 5
 |  |  Argentina | 4
 | 1
 | 0
 | 3
 | 50
 | 54
 | -4
 | 2
 |  |  Uzbekistan | 4
 | 0
 | 0
 | 4
 | 10
 | 139
 | -129
 | 0
 | 
 Group BCentral European Summer Time (GMT +2)
United States  12 - 7  Slovakia
Quarter-by-Quarter: 5-4, 0-0, 6-3, 1-0
August 28th 2021, h. 1:00, Swimming Complex Podoli, Prague 
 
Serbia  28 - 0  Czech Republic
Quarter-by-Quarter: 8-0, 6-0, 6-0, 8-0
August 28th 2021, h. 13:30, Swimming Complex Podoli, Prague Czech Republic  2 - 18  United States
Quarter-by-Quarter: 0-5, 1-5, 1-8, 0-0
August 29th 2021, h. 09:00, Swimming Complex Podoli, PragueSpain  6 - 6  Serbia
Quarter-by-Quarter: 1-1, 2-2, 2-2, 1-1
August 29th 2021, h. 10:30, Swimming Complex Podoli, Prague Slovakia  10 - 5  Czech Republic
Quarter-by-Quarter: 2-2, 3-1, 4-1, 1-1
August 30th 2021, h. 15:00, Swimming Complex Podoli, Prague United States  10 - 20  Spain
Quarter-by-Quarter: 3-6, 2-3, 4-7, 1-4
August 30th 2021, h. 16:30, Swimming Complex Podoli, Prague Spain  15 - 5  Slovakia
Quarter-by-Quarter: 4-2, 4-2, 4-1, 3-0
August 31st 2021, h. 15:00, Swimming Complex Podoli, PragueSerbia  14 - 9  United States
Quarter-by-Quarter: 4-1, 3-2, 3-2, 4-4
August 31st 2021, h. 16:30, Swimming Complex Podoli, Prague Slovakia  0 - 15  Serbia
Quarter-by-Quarter: 0-2, 0-5, 0-4, 0-4
September 1st 2021, h. 12:00, Swimming Complex Podoli, PragueCzech Republic  4 - 18  Spain
Quarter-by-Quarter: 1-4, 0-2, 3-5, 0-7
September 1st 2021, h. 13:30, Swimming Complex Podoli, Prague 
Group B Final Standing
| Team | P | W | D | L | GF | GA | +/- | Pt. |  |  Spain | 4
 | 3
 | 1
 | 0
 | 59
 | 25
 | +34
 | 7
 |  |  Serbia | 4
 | 3
 | 1
 | 0
 | 63
 | 15
 | +48
 | 7
 |  |  United States | 4
 | 2
 | 0
 | 2
 | 49
 | 43
 | +6
 | 4
 |  |  Slovakia | 4
 | 1
 | 0
 | 3
 | 22
 | 47
 | -25
 | 2
 |  |  Czech Republic | 4
 | 0
 | 0
 | 4
 | 11
 | 74
 | -63
 | 0
 | 
 Group CCentral European Summer Time (GMT +2)
Germany  14 - 4  Egypt
Quarter-by-Quarter: 5-1, 3-0, 3-2, 3-1
August 28th 2021, h. 15:00, Swimming Complex Podoli, Prague Brazil  10 - 22  Hungary
Quarter-by-Quarter: 1-6, 1-4, 4-6, 4-6
August 29th 2021, h. 12:00, Swimming Complex Podoli, PragueGermany  14 - 5  Brazil
Quarter-by-Quarter: 1-1, 3-0, 5-2, 5-2
August 30th 2021, h. 09:00, Swimming Complex Podoli, PragueBrazil  9 - 8  Egypt
Quarter-by-Quarter: 2-3, 2-4, 1-1, 4-0
August 31st 2021, h. 18:00, Swimming Complex Podoli, PragueHungary  12 - 5  Germany
Quarter-by-Quarter: 3-2, 2-1, 5-0, 2-2
August 31st 2021, h. 12:00, Swimming Complex Podoli, PragueEgypt  3 - 22  Hungary
Quarter-by-Quarter: 0-5, 1-2, 0-8, 2-7
September 1st 2021, h. 15:00, Swimming Complex Podoli, PragueGroup C Final Standing
| Team | P | W | D | L | GF | GA | +/- | Pt. |  |  Hungary | 3
 | 3
 | 0
 | 0 | 56
 | 18 | +38
 | 6
 |  |  Germany | 3
 | 2
 | 0
 | 1
 | 33
 | 21
 | +12
 | 4
 |  |  Brazil | 3
 | 1
 | 0
 | 2
 | 24
 | 44
 | -22
 | 2
 |  |  Egypt | 3
 | 0
 | 0
 | 3
 | 15
 | 45
 | -30
 | 0
 | 
 Group DCentral European Summer Time (GMT +2)
South Africa  5 - 16  Montenegro
Quarter-by-Quarter: 1-3, 0-6, 1-3, 3-4
August 28th 2021, h. 16:30, Swimming Complex Podoli, Prague 
Greece  26 - 2  Kazakhstan
Quarter-by-Quarter: 6-0, 8-1, 8-0, 5-1
August 29th 2021, h. 13:30, Swimming Complex Podoli, Prague South Africa  5 - 21  Greece
Quarter-by-Quarter: 3-6, 0-3, 2-5, 0-7
August 30th 2021, h. 10:30, Swimming Complex Podoli, PragueGreece  8 - 9  Montenegro
Quarter-by-Quarter: 1-1, 3-3, 2-2, 2-3
August 31st 2021, h. 09:00, Swimming Complex Podoli, Prague Kazakhstan  8 - 10  South Africa
Quarter-by-Quarter: 0-1, 2-2, 4-6, 2-1
August 31st 2021, h. 10:30, Swimming Complex Podoli, Prague Montenegro  13 - 2  Kazakhstan
Quarter-by-Quarter: 3-0, 5-0, 4-2, 1-0
September 1st 2021, h. 16:30, Swimming Complex Podoli, Prague Group D Final Standing
| Team | P | W | D | L | GF | GA | +/- | Pt. |  |  Montenegro | 3
 | 3
 | 0
 | 0
 | 38
 | 15
 | 23
 | 6
 |  |  Greece | 3
 | 2
 | 0
 | 1
 | 55
 | 16
 | +39
 | 4
 |  |  South Africa | 3
 | 1
 | 0
 | 2
 | 20
 | 45
 | -25
 | 2
 |  |  Kazakhstan | 3
 | 0
 | 0
 | 3
 | 12
 | 49
 | -37
 | 0
 | 
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