Reigning men's Olympic hockey champions Belgium beat New Zealand 2-1 on Sunday as the Red Lions took the lead in the Pool B standings after a twisting shot found the top corner of the goal, salvaging the win after a sluggish performance.
India and Australia also have three points and have a chance to tie Belgium for the top Pool B spot in their games against Argentina and Ireland respectively on Monday.
"I think we didn't perform at our best level today. But I also think it's a bit normal at the Olympics. You're not going to perform every time at your best," said Florent van Aubel who netted the game winner shortly after New Zealand's equaliser.
"We know we're a very good team, very good players. Everybody has an amazing skill level. Everything just has to come together," Florent said.
New Zealand now have two losses to start the tournament, which puts them at the bottom of Pool B with three games to go.
The other afternoon match saw the Spanish men's team post a 2-0 upset of World Cup winner Germany in Pool A to keep their chances alive after a blowout loss to Britain on Saturday left them reeling.
Second-ranked Britain avoided an upset by South Africa as a last-gasp goal off a set piece forced a 2-2 draw in Pool A.
The top-ranked Netherlands thrashed hosts France 4-0 in the other Pool A game and are top on six points.
Early matches were closer on Sunday than on the opening day of the tournament, with all but one game being decided by one goal apart from the German women's team 2-0 victory against Japan.
The Australia women's team beat South Africa 2-1 while Spain's women's team defeated Britain 2-1 in tightly contested matches.
The fourth-ranked Belgian women opened their tournament in the morning with a 2-1 victory against Pool A opponent China after a top-net shot in the dying minutes secured the game off a deep ball and some quick passing between the forwards.
"I have always been a team player, but of course it's always nice to score a goal in an opening game for this kind of tournament," scorer Charlotte Engelbert said.
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