KASHIMA, Japan, July 22 (Yonhap) -- The math in football is simple. You have to score more than the other team. Every other number, whether it's shots or passes or ball possession, ultimately doesn't matter.

South Korea learned that the hard way on Thursday, as they fell to New Zealand 1-0 in Group B action at the Tokyo Olympic men's football tournament despite holding sizable advantages in other statistics. South Korea outshot New Zealand 12-2, and had the ball 63 percent of the time.

Chris Wood scored the second-half winner at Ibaraki Kashima Stadium in Kashima, northeast of Tokyo. He put the ball into the net in the 70th minute, when the goal was called back on an offside ruling. The on-field decision was overturned and Wood was credited with the goal in the 76th minute.

The play came off an unlucky bounce for South Korea. Joe Bell's shot from midrange hit defender Jeong Tae-wook and the ball found the wide-open Wood, who easily put it past goalkeeper Song Bum-keun.

It may be tempting to blame that bad luck for South Korea's loss, but that would let the team off the hook for missing a few chances to score early and put the match out of reach.

Striker Hwang Ui-jo had a glorious opportunity with his 41st-minute header, and goalkeeper Michael Woud made the stop on the low shot. Kwon Chang-hoon wasted two volley attempts in the first half -- first swinging and missing on the ball in the goalmouth and then sending the ball wide of the target.

Hwang and Kwon are two of the three overage players at this under-24 tournament. They were selected precisely for their offensive ability. There is very little room for error now that matches count. The opening loss put South Korea in an unexpected hole -- despite Wood's presence as a dangerous scorer with Premier League credentials, New Zealand were seen as the weakest team in the group -- going into Sunday's match against Romania.

Things looked promising for South Korea in the opening minutes. Their heavy ball pressure forced a few New Zealand turnovers deep in the Kiwi zone, leading to dangerous-looking passes into the box.

But in the hot and humid conditions, that style of play wasn't going to be sustainable. South Korea had to capitalize on early opportunities and make New Zealand chase the game.

Instead, once the match slowed down, New Zealand started creeping into the attacking zone. They didn't have a shot in the first half and then scored on their only shot on target.

Hwang said it falls on attackers, like himself, to be more opportunistic around the net.

"We should have made life easy on ourselves after generating all those chances. We forwards have to be better in the next match," Hwang said. "It'll be important for us to score early and lessen the pressure on our defenders."

As for his first-half header, Hwang said, "I didn't get enough of it. It's extremely disappointing. But I had a few other chances that I should have converted."

Kwon said the New Zealand goal came at an unexpected moment in the match, and that the final score wasn't a true reflection of his team's effort.

"Giving up a goal doesn't fall on any individual. It's on the whole team," Kwon said. "We have to regroup mentally and physically, so we can win the next match."

South Korea coach Kim Hak-bum apologized to fans for letting them down, but said his team still has a shot at reaching the quarters.

Kim also offered a harsh review, saying, "I don't think there is anything that our players did well."

"I told the players to look for open space up the middle and make passes in that direction, but they couldn't execute that at all," the coach said. "The guys had to be more aggressive. I think they were too wound up because this was the first match. We should address that but this is only one match. We'll be fine in later matches."

Midfielder Lee Kang-in said he was "really disappointed" with the loss but he has no choice but to look forward.

"In football, you can win some and you can lose some. I'll have to forget about this one and get ready for the next one," Lee said. "I don't have much else to say, other than that we'll try to win the next one."

Source: Yonhap News Agency