The eastern portion of the Königsberg defenses was the only part that was fully manned, while the approaches from the south were entirely open. Then the new commanders raised the stakes dramatically. They must do more than stop Samsonov in his tracks, as they had tried to block and push back Rennenkampf. Samsonov must be annihilated before they turned back to deal with Rennenkampf. For the moment Samsonov would be opposed only by the forces he was already facing, XX Corps, mostly East Prussians who were defending their homes. The bulk of the Second Russian Army was still coming towards the front; if necessary, they would be allowed to push further into the province while the German reinforcements assembled on the flanks, poised to encircle the invaders—just the tactics instilled by Schlieffen. The danger was that if Rennenkampf's First Army marched southwest they would appear on the Eighth Army's extreme left flank. Thanks to their consolidation, the coming battle would be fought with 1.8 Russians facing each German. OHL was informed that they were moving to envelop the invaders. Zhilinskiy had agreed to Samsonov's proposal to start the Second Army's advance further westward than originally planned, separating them even further from Rennenkampf's First Army. On 22 August Samsonov's forces encountered Germans all along their front and pushed them back in several places. Zhilinskiy ordered him to pursue vigorously. They already had been advancing for six days in torrid heat without sufficient rest along primitive roads, averaging a day and had outrun their supplies. On 23 August they attacked the German XX Corps, which retreated to the Orlau-Frankenau line that night. The Russians followed, and on the 24th they attacked again; the now partially entrenched XX Corps temporarily stopped their advance before retreating to avoid possible encirclement. At one stage the chief of staff of the corps directed artillery fire onto his own dwelling. Samsonov saw a wonderful opportunity because, as far as he was aware, both of his flanks were unopposed. He ordered most of his units to the northwest, toward the Vistula, leaving only his VI Corps to continue north towards their original objective of Seeburg. He did not have enough aircraft or skilled cavalry to detect the German buildup on his left. Rennenkampf mistakenly reported that two of the German Corps had sheltered in the Königsberg fortifications. On 24 August Hindenburg, Ludendorff and Hoffmann motored along the German lines to meet Scholtz and his principal subordinates, sharing the roads with panic-stricken refugees; in the background were columns of smoke from burning villages ignited by artillery shells.