Agha a mere n'agbata ụbọchị 17 na 19 Septemba 1639 mgbe otu ndị agha Dutch n'okpuru Admiral Maarten Tromp na Admiral Witte Corneliszoon de With, zutere ọtụtụ ndị agha Spanish n'okpuru Antonio D'Oquendo, nke gụnyere ndị agha 40 ruo 45 na ụgbọ mmiri 40 ruo 50 jupụtara na ndị agha Spanish 13,000 ndị a na-ebugharị na Dunkirk. Tromp na ụgbọ mmiri 12 hụrụ ụgbọ mmiri Spanish na 16, mana chere ka de With bịarute na ụgbọ mmiri ise ọzọ tupu ịwakpo. N'agbanyeghị na ọ dị obere, Tromp nwetara aka elu n'ọgụ nke na-aga n'abalị. N'echi ya, Zeeland Commodore Joost Banckert rutere iji wusie ndị Dutch ike na ụgbọ mmiri 12 ọzọ.
Agha nke Downs, ebe e meriri D'Oquendo n'ụzọ siri ike.