While the army of the Ottomans and its Crimean Tatar vassals greatly outnumbered the Russian force opposite them, the Russian commander, Field Marshal Pyotr Rumyantsev, deftly arranged his far smaller army in solid infantry squares and surprisingly chose to go on the offensive against the allied forces.

The Ottoman sultan did not expect such a calamity to happen, but this shocked the Grand Vizier Ivazzade Halil Pasha even more that he had lost oversight of the overall situation in the theater and thus let the initiative pass to the enemy for the time being.

The Turkish troops, positioned on the heights of the Cahul River's left bank in a fortified camp east of the village of Vulcănești, were preparing to launch a frontal attack on the Russian army.

After some time in preparation and deliberation, the Grand Vizier returned to the theater and managed to reinforce his army, which had been gravely depleted after several crushing battlefield defeats.

Although the Ottoman army was undoubtedly the far larger and better equipped one compared to the medieval-style Crimean Tatar force, it was also the nearest for the Russians within the nearest marching distance to engage as to not aggravate the already worsening supply situation which he tried so hard to resolve by issuing 10-days worth of thriftily chosen rations to each soldier after resupplying shortly after the Larga battle, therefore neglecting his own supply lines but at the same time providing provisional sustenance to his men up into the coming battle.

The smaller Russian force of about 40,000 led by Rumyantsev was marching towards Cahul, with the Ottoman camp only 7 miles (11 km) away, positioned at the right side of the Kagul River.

Ivazzade Pasha witnessed the marching of this force, and after doing a reconnaissance on the Russian positions, decided that he would launch his attack the next day at precisely 10 a.m., two hours before noon.

With this chronological discrepancy in the plans of commanders of both sides, the Russians were sure to achieve the element of surprise against the enemy the moment they launched their attack.

The said cannons fired grapeshots to the Ottoman cavalry, inflicting seriously crippling losses to the attackers and were thus driven back with only relatively few remaining to report to their commanders, and thus the Russians continued their fighting march.

Fearing to lose his line of retreat, Ivazzade Pasha rushed all available Ottoman units to the entrenchments, only to be torn apart and driven out by constant, devastating and accurate fire of the Russian artillery.

At this time General Repnin's troops reached the heights south of the enemy camp and opened a rifle and artillery fire on it from the rear.

The huge yet disheartened Tatar army along with the Crimean Khan, having not participated in the battle at Kagul the previous day despite only an hour's march away, instead retreated towards Ackerman located on the Crimean homeland, having accomplished nothing positive thus far and giving zero contribution on the Ottoman war effort for the rest of the war.

Russia's victory in the Battle of Kagul opened the way to the Danube for its troops and was a testament to the commanding skills of P. A. Rumyantsev, who applied his main principle of breaking the enemy by offensive actions.