Due to threat from Poland, the front with the Soviets was quiet for more than a month. There were minor incidents involving scouts or outpost guards. The Red Army used the time to reorganize and strengthen their forces, using natural barriers, like plentiful lakes, rivers, and hills, enhanced with trenches and barbed wires, to secure their position. They also had fortifications built during World War I about 10 km (6.2 mi) south of Daugavpils. The Soviets had larger forces: Lithuanians had two infantry regiments and five separate battalions; the Soviets had six regiments and one separate battalion. The Lithuanians together with Poles planned to push for Daugavpils starting August 9, but the plans were delayed until August 23.
The Ukmergė Group attacked first and captured Zarasai on August 25. The Group moved about 30 km (19 mi) into the Soviet-controlled territory, but neither its right or left flanks were adequately protected by the Polish units or the Panevėžys Group. The Panevėžys Group began its advance on August 26 and Polish troops moved along the railroad towards Turmantas. The Lithuanians maneuvered around the old Russian fortifications, forcing the Red Army to retreat. Converging on Daugavpils, the Lithuanian–Soviet front shortened and the Lithuanians were able to concentrate their forces. On August 28, the Soviets began retreating north across the Daugava River. By August 31, on the southern shore of the Daugava, the Soviet held only Grīva, a suburb of Daugavpils.
The enemy was driven out from the Lithuanian territory and the narrow front stabilized as Lithuanians and Soviets were separated by the Daugava River. The Lithuanian main forces could be redeployed elsewhere, including protection of the demarcation line with Poland and planned attacks against the Bermontians in northern Lithuania. In September 1919, joint Polish and Latvian forces took the southern shore of Daugava, including Grīva. The Lithuanian–Soviet front remained open until the Battle of Daugavpils when Latvian and Polish forces captured Daugavpils in January 1920. The Lithuanians did not participate in these operations. The Lithuanians claimed the territory, taken by their soldiers, for themselves despite Latvian protests. This led to several skirmishes between Latvian and Lithuanian troops, but the border issue was successfully mediated by Britain and finally resolved in March 1921.