COVENTRY, United Kingdom - For a game and a half of the London Olympics, the face of women's soccer in Canada had been largely invisible.

But team captain Christine Sinclair charged back into the spotlight Saturday, scoring two second-half goals to lead the Canadians to a 3-0 victory over South Africa for their first victory of the Games.

"That's the player she is, you can contain her for a period of time, and when she's on, she's on," said Canadian coach John Herdman. "I think that's the mark of those truly great players, there's just some days they're unstoppable. . . That will give her the confidence to keep moving on."

Melissa Tancredi also scored for the No. 7 Canadians in a victory that brought them closer to a spot in the quarter-finals.

The Canadians, who were coming off a 2-1 loss to Japan three nights earlier, meet No. 4 Sweden to wrap up the preliminary round on Tuesday, and need to finish top-two in their pool — or be one of the two best third-place teams — to move on.

"Every game we try to tick a box, we ticked our box today," Herdman said. "We know Sweden is sitting in front of us, it's going to be a different game, different approach. . . Wish we could have got an extra goal which could help later on in the tournament."

Sweden and Japan — with a win and tie apiece — played to a 0-0 draw in Saturday's early game at City of Coventry Stadium. If the determining factor for the quarter-final qualifiers comes down to goal difference, Sweden has one more than Canada.

Sinclair recorded goals No. 138 and 139 of her career, on her dad Bill's birthday.

"I totally forgot to do my celebration for him," she said laughing. "I was going to do a little heart (with her hands) for him and I totally forgot."

She collected her first in the 58th minute when she got her head on a cross from Lauren Sesselmann. The ball appeared to cross the line, but the Canadian captain— who has 19 goals in 18 games this year alone — sprinted in to pounce on the rebound, banging the ball into the net.

The 29-year-old added her second in the 86th minute, running onto a lovely through ball from Sophie Schmidt to beat goalkeeper Thokozile Mndaweni one-on-one.

Sinclair has always been the pivotal point of Canada's offence, but Herdman has focused on getting others involved. He said the team no longer succeeds or fails on the shoulders of its captain.

"I think that's taken a bit of weight off Christine's shoulders," the coach said. "You're starting to see it's a bit more than Christine. We've relied on her for too long, there's other players who could have scored today as well. I'm hoping through the tournament Christine will come forth when she needs to.

"There was certainly a moment in the game we hoped Christine would step up and she did."

Tancredi collected her second goal of the Games in the seventh minute, one-timing a cross from Diana Matheson past Mndaweni.

Despite the wide gap in world rankings and international experience, 61st-ranked South Africa gave the Canadians a challenge in the first half in front of an announced crowd of 14,753 at City of Coventry Stadium.

Banyana Banyana — "The Girls" — are making their Olympic debut and have also never played in a World Cup. But for big chunks of the first 45 minutes they took advantage of a sloppy Canadian side while Herdman looked frazzled, hands-on-hips, on the sidelines.

A messy moment of miscommunication between Robyn Gayle and 'keeper Karina LeBlanc almost led to a South African goal in the 31st minute. Neither Canadian went to the ball, allowing Mpumi Nyandeni to take a shot that bounced off Gayle's foot and looped off the crossbar.

It was exactly the kind of game that maybe a year ago would have had the Canadians crumbling under the pressure.

"I think we may have freaked out just folded under the pressure," Tancredi said. "Especially defensively. I think we did a great job defensively to just be calm on the ball. We were on the ball, we slowed it down, we played passes, we were simple and that's all we needed at that time."

The Canadians put the pedal down in the second half, dominating possession against a tiring South African side.

Canada's back line took another blow late in the game, however, when Gayle was helped off the field with a hamstring injury. The Canadians were already missing defenders Candace Chapman and Emily Zurrer due to injuries.

Sweden poses a much tougher test. The Swedes were bronze medallists at last summer's World Cup and 4-1 winners over South Africa in their opener.

"They know how to win football matches, they're very organized, disciplined," said Herdman, who heads to his hometown of Newcastle for Tuesday's game. "That team has been together longer, doing the things they do for longer, under the same coach. Our team is still learning certain things game to game."

Herdman, who was hired as Canada's head coach last fall after its disastrous performance at the World Cup, made two changes to his lineup from Wednesday's game, substituting LeBlanc in net for Erin McLeod, and replacing Chapman with Gayle. Chapman left Wednesday's game with a calf injury.

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