This was Osterman-Tolstoy with two divisions of infantry and two of cavalry. His orders were simple, stop Vandamme's advance, whatever the cost. Reinforcements would be sent as they became available.
On his left flank Osterman has Rosen's Russian Guard division of 6 battalions with two heavy batteries deployed between the villages of Straden and Priesten. Between Priesten and the southern road to Teplitz are Pischnitsky's understrength division of II Corps (6 weakened battalions) and Pahlen's light cavalry (3 light regiments and 1 dragoon regiment). Expected Russian reinforcements are Schachafskoi's infantry division and the 2nd Cuirassier division.
Steve took the part of Vandamme and faced the same problem, wait for all his forces to deploy and risk the Allied force becoming stronger, or, attack with what troops he had present. He decided on the latter, (just like Vandamme) and after a short bombardment Revest's infantry moved forward with orders to seize the village of Straden. Dupas was to attack Priesten and Chastel move south to counter the threat of Pahlen.
In front of Priesten, Pischnitsky's men deployed to meet Dupas' men as they advanced from Kulm. The long column of Frenchmen were subjected to the fire from the 12lb batteries as they neared the bridge over stream. Nevertheless they pressed on and soon were massing for an attack on the Ashperon regiment which formed Pischnitsky's front line
Although effective, the charge by the Russian cavalry had left a hole in the Russian line. What Osterman had not seen when he ordered the attack was the approach of Gorbrecht's light cavalry. Vandamme had directed them to support Revest's infantry, who had tried and failed a second time to wrench Straden from the grip of the Russian guards. As Gorbrecht moved forward he had seen the Russian cavalry attack and the lack of reserves to cover the Russian centre whilst the Russian cavalry reformed. All that lay before him were two batteries of guns, eliminate those and the road to Teplitz was open. With the Polish hussars in the van, the light cavalry moved forward.
On the southern flank Chastel had moved round the village of Karwitz and deployed to attack Pahlen. His approach had been subjected to fire from Pahlen's horse artillery, but only light losses had been suffered. Bugles blared and the two divisions of light cavalry closed to melee. It was at this point that fortune favoured the Russians. All three melees were won by the Russians and the margins were so extreme that all three units were destroyed. The subsequent divisional morale roll also came up as '1' so the remaining units also left the field. With the southern flank secure, Pahlen could be redeployed to the centre, perhaps in time to thwart Gorbrecht.
Unfortunately, we ran out of time at this point, which was a shame as the battle was so finely balanced. Revest's men were hanging on in the north and had inflicted some damage on the Russian Guard. Dumonceau's division was at Kulm and following Gorbrecht towards the Tepltz road. Schavitch's Light Cavalry needed time to recover and Pischnitsky's division was nearing a morale test, being worn down by Dupas' attack. Schachafskoi's infantry division would arrive in two moves time to support the centre and Priesten. The Cuirassier division was still some way off.