By September 1652 the English Commonwealth's Council of State had grown overconfident. After the English victory at the Battle of the Kentish Knock in late September, they assumed the Dutch would simply stand down for the winter. Ships were sent off to the Mediterranean and the Baltic; the biggest English warships went into repair. Sailors with months of unpaid wages deserted or rioted on the docks. The Dutch, meanwhile, were doing the opposite. Their merchant interests required one more convoy run south before the season closed, and Lieutenant-Admiral Maarten Tromp was reinstated as supreme commander after Vice-Admiral Witte de With's nervous breakdown following the Kentish Knock defeat. Tromp sailed from Hellevoetsluis on 21 November Old Style with 88 men of war, five fireships, and a vast convoy of 270 merchantmen bound for France, the Mediterranean, and the Indies. Gales drove him back; he tried again two days later. The English Channel was about to host a battle that the English very much did not want to fight.

Blake had 42 capital ships and ten smaller vessels anchored in the Downs, between North Foreland and South Foreland - a defensive position that ought to have been safe. A council of war on 29 November decided to avoid action; Blake may not have realised how large Tromp's fleet really was. The English upped anchor and ran south. Northwest winds funnelled them along the Kentish coast and out toward Dover. By the next afternoon the geometry of the Channel was working against them. The curve of the shoreline forced the English onto a southerly course past the Dungeness cape - the great triangle of shingle that pokes out into the strait - and through the narrow channel between Dungeness and the Varne Bank. Blake hoped to slip through it ahead of the Dutch. He arrived to find seventeen Dutch ships already waiting on the far side.

Around three in the afternoon the first ships engaged. Blake's flagship Triumph cleared the exit; Tromp's Brederode arrived almost simultaneously and ran up the bloodflag, the red signal for general attack. Blake tacked across the Dutch flagship's bow and fired a broadside; Tromp returned the favour. The English Garland tried the same manoeuvre next but rammed Brederode's bow with such force that the Dutch ship's bowsprit broke off and the two hulls became locked together. Tromp's larger crew swarmed aboard; Tromp promised 500 guilders to the first man to strike the English flag. One Dutch sailor climbed the mainmast and replaced the St George's Cross with the Prince's Flag. In despair, captain Richard Batten blew up his own upper deck to drive away the boarders. The Anthony Bonaventure came up to help, grappled Brederode's port side, and was in turn boarded by Vice-Admiral Johan Evertsen's Hollandia. Four ships locked together in the swell, with hand-to-hand fighting raging across all of them. The entire crew of the Anthony Bonaventure, including Captain Walter Hoxton, was killed. Tromp's secretary was shot dead beside him. "Children," Tromp shouted to his combined crews, "things cannot go on this way. It's them or us!"

The narrow exit that had trapped the English also constrained the Dutch. Commodore Michiel de Ruyter took his Witte Lam through the gap in the wrong direction, hoping to attack the English mass from inside, but no one followed him and he had to withdraw. "If we had had any help," he complained in his journal, "yea of but ten or twelve ships, we would have beaten the entire fleet." Most of Tromp's fleet was still waiting outside the bottleneck. Two heavily armed English ships, the Vanguard and the Victory, used their superior firepower to break the Dutch line and let Blake retreat with the wounded Triumph - her fore-topmast shot away, Blake himself injured. Around five o'clock the November darkness closed in and the battle ended. Five English ships were lost: the captured Garland and Anthony Bonaventure both taken into Dutch service, two smaller vessels burnt including possibly the light frigate Acorn, and one sunk. The Dutch lost the Schiedam to fire and explosion that evening. Blake slipped back to the Downs in the dark.

Tromp could not be satisfied. He had missed a chance to annihilate the English fleet completely; the Dutch had won, but not finally. He briefly considered following Blake up the Medway estuary, but despite offering a reward of fifty Flemish pounds, no pilot in the entire Dutch fleet would risk navigating those tricky waters. Not until 1667 would De Ruyter manage the famous Raid on the Medway. The English reforms that followed Dungeness were more lasting than the battle itself. Part of Blake's force had consisted of impressed merchantmen still commanded by their civilian owners - many of whom had simply refused to fight. Some naval captains insisted on the traditional right to leave the battle whenever they liked to chase prizes. Blake threatened to resign. The Lords Commissioners of the Admiralty responded by placing all impressed vessels under naval command and issuing new Sailing and Fighting Instructions - the rulebook that would govern Royal Navy fleet actions for two centuries. There is a legend that Tromp tied a broom to his mast to show he had swept the sea clean. The Royal Navy historian N.A.M. Rodger doubts it - boasting was out of character for Tromp, a broom signalled a ship for sale, and no Dutch source mentions it. The broom is probably someone else's story.