 On 2 July and through the next six days , a rainstorm typical of Belarusian summers slowed the progress of the panzers of Army Group Center , and Soviet defenses stiffened . The delays gave the Soviets time to organize a massive counterattack against Army Group Center . The army group 's ultimate objective was Smolensk , which commanded the road to Moscow . Facing the Germans was an old Soviet defensive line held by six armies . On 6 July , the Soviets attacked the 3rd Panzer Group with 1000 tanks . The Germans defeated this counterattack with overwhelming air superiority . The 2nd Panzer Group crossed the Dnieper River and closed in on Smolensk from the south while the 3rd Panzer Group , after defeating the Soviet counterattack , closed on Smolensk from the north . Trapped between their pincers were three Soviet armies . On 18 July , the Panzer Groups came to within sixteen kilometres of closing the gap , but the trap did not snap shut until 26 July . When the Panzer Groups finally closed the gap , 300 @,@ 000 Red Army soldiers were captured , but 200 @,@ 000 Red Army soldiers escaped to stand between the Germans and Moscow . 
