Igor Vori's late goal helped guide Croatia to victory
Croatia began the defence of their Olympic crown with two late goals securing a 31-29 victory over Spain on the opening day of the men's handball.
Germany, world champions in 2007, beat South Korea in another close game, four late goals seeing them win 27-23.
China were outclassed in losing 33-19 to Poland, while Russia lost 33-31 to Iceland.
France achieved a 34-26 victory over Brazil, and honours were shared between Denmark and Egypt, who tied 23-23.
Croatia looked as though they would have to settle for a point against Spain, before Igor Vori and Domagoj Duvnjak scored in the final minutes to secure the two points.
Florian Kehrmann snatched four goals in the last five minutes to guarantee an opening day victory for the Germans, while Snorri Steinn Gudjonsson was on top form for Iceland, scoring 12 times as they beat the 2004 bronze medallists.