 After Kiev , the Red Army no longer outnumbered the Germans and there were no more trained reserves directly available . To defend Moscow , Stalin could field 800 @,@ 000 men in 83 divisions , but no more than 25 divisions were fully effective . Operation Typhoon , the drive to Moscow , began on 2 October . In front of Army Group Center was a series of elaborate defense lines , the first centered on Vyazma and the second on Mozhaysk . 
