Alexander Kerzhakov scored with one of his first touches after coming on as a substitute to earn Russia a 1-1 draw with South Korea in a World Cup match marked by the first big goalkeeping error of the tournament.
Having lost four of their last five games heading to Brazil, the South Koreans came into their eighth straight World Cup with concerns over their flimsy defence and a lack of goal threat.
A 4-0 thrashing by Ghana in a warm-up in Miami last week highlighted those worrying deficiencies perfectly.
However, South Korea couldn't hold on and when Dzagoev's cross-shot was spilled out by goalkeeper Jung Sung-ryong and Hwang Seok-ho's clearance went straight at Andrei Yeshchenko, Kerzhakov was on hand to bundle home from inside the six-yard box.
Russia goalkeeper Igor Akinfeev spilled Lee Keun-ho's speculative long-range shot into his own net to gift South Korea a 68th minute lead at the Arena Pantanal in Cuiaba in Group H.
Akinfeev stayed on the ground inside his own net, head in his hands, after making his blunder, clearly embarrassed after dropping what was a routine save from a shot from about 30 yards.
The explosive six-minute spell that featured both goals was not in keeping with the rest of a fairly mundane game characterised by slow build-up play, poor passing and wayward finishing.
A point leaves both teams behind Belgium, who beat Algeria 2-1 earlier, but the group appears wide open based on the opening two fixtures.