Horna, who had orders to join with his ships Admiral Antonio de Oquendo's fleet at A Coruña, escorted at the same time a transport convoy carrying 2,000 Walloon soldiers to Spain, where they were needed.

[7] In January 1639 the Count-Duke of Olivares ordered a great fleet to be gathered at the Galician port of A Coruña with the aim of carrying troops and money to the Spanish Netherlands.

The recently recruited Walloon Tercio of the Baron of Molinguen, whose strength was about 2,000 men, was embarked aboard the Dunkirk Squadron in order to be transported to Spain to face an imminent French attack in the north of the country.

[3] The Marquis of Fuentes, military governor of the town, categorically ordered Miguel de Horna to sail without delay, not fearing the Dutch squadron because of its smaller strength.

[3] The Spanish convoy, consisting of 12 galleons, 3 pinnaces, and 5 transports,[3] departed the port at dawn on 18 February via a southern outlet called Het Scheurtje (The Little Fissure).

[10] Tromp followed him and engaged the vice-flagship of Dunkirk, which had lost the use of its steerage and had its rudder-head shot, being finally run aground upon the western tail of the Splinter, where its crew set it on fire after salvaging some of the provisions that it had aboard.

[6] De Horna, strategically if not tactically, had accomplished his mission,[1] while Tromp's 2-year blockade of Dunkirk had failed to prevent the Spanish ships from continuing to undertake their activities.