On the crucial day during battle on Sutjeska in 1943, the enemy encircled the main Partisan forces by heavy offensive, leaving only a narrow passage on Zelengora, between Ljubin grob and Kosuta. Strategically and morally, the extremely important battle was going on at Ljubin grob peak elevation. Members of second detachment, the Third battalion of the Fourth Montenegrian Proletarian brigade, took over the mission to guard the passage for 24 hours. Although much weaker than the enemy, they fulfilled their mission with great losses.