The Canadian captain calmly stroked home a penalty in stoppage time Saturday to give Canada a 1-0 win over a young Chinese side in the opening match of the Women's World Cup.
The decisive penalty was called after Adriana Leon went down after contact with defender Zhao Rong.
"The first thing that went through my head is 'I'm taking this. I've been practising my whole life for that moment,'" said Sinclair. "Then the next thing through my head was man, the fans are very loud right now."
The crowd of 53,058 — and perhaps the better part of a nation outside of Commonwealth Stadium — exhaled after Sinclair sent the ball deep into the corner past a diving Wang Fei.
"I don't know if she could have go any closer to that post," midfielder Sophie Schmidt said admiringly.
It was Sinclair's 154th goal in 224 international appearances . And it came in the 92nd minute, with three minutes up on the fourth official's board for stoppage time.
"Cometh the hour, cometh the woman," coach John Herdman said. "Outstanding from Christine Sinclair, the sort of pressure (there was) on her. There's only one woman in the world that can get up and do that.
"Good start for Canada. Three points in the bag. Exactly where we wanted to be."
Put perhaps not how he drew it up. The game had seemed to be destined to end at 0-0 with Canada unable to fire on all cylinders against a China side that would have been delighted with a draw.
Sinclair has now scored in four World Cups, pushing her tournament total to eight.
For Canada, it was three points and a bullet dodged after Herdman switched to a more offensive 3-4-3 formation late in the game. A draw would have been two points lost in a tournament with little margin for error.
Canada is ranked eighth in the world, compared to No. 16 for China.
While Sinclair administered the coup de grace, her teammates set the scene by coming at China in waves.
The penalty changed everything. "I nearly cried on the touchline," Herdman said.
"And when the call came, I celebrated like we'd just scored," he added. "Because I knew there was only one woman who was going to step up in the 90th minute and write the script. Like she always does. And she did."
Herdman called it a brave call by Ukraine referee Kateryna Monzul. China coach Hao Wei was classy in defeat, saying he needed to see the video of the incident but respected the referee's calls.
After she scored, an emotional Sinclair broke into a celebration run. Destination unknown.
"I had no idea. I was running fast and I just saw John. I've never seen him squat that low before so I thought he deserved a hug."
It quickly turned into a group hug.
The Canadians had earlier chances but failed to execute and, after a strong start, let the Chinese back into the match before an enthusiastic crowd. Both teams hit the woodwork in the first half.
Canada had 62 per cent of possession and outshot China 14-5 (4-1 in shots on target).
Happy ending aside, Sinclair called it a frustrating game with China dropping back in defence and constantly wasting time. Herdman, despite his wide smile, acknowledged Canada had snuck a win against a side playing for a draw.
His substititions helped turn the tide.
Herdman replaced Jonelle Foligno with Kaylyn Kyle in the 61st minute, pushing Schmidt up higher. Ten minutes later he traded muscle for flair, bringing off hard-nosed Desiree Scott for teenage midfielder Jessie Fleming.
The last roll of the dice was Leon for Tancredi in the 77th minute.
The crowd booed what it saw as China's efforts to waste time as the clock wound down.
The previous attendance record for a Canadian national team match on home soil was 51,936, set June 5, 1994, when the Canadian men played Brazil at the same venue.
Sinclair called the Commonwealth Stadium atmosphere the best she had ever played before in Canada.
Canada's next game is Thursday against No. 17 New Zealand, which played the 12th-ranked Netherlands in the second game of Saturday's Group A doubleheader.
The tournament spotlight switches Sunday to Ottawa where No. 29 Thailand and the 67th-ranked Ivory Coast face No. 11 Norway and No. 1 Germany, respectively, in Group B play.
The game, under sunny and breezy 26-degree Celsius conditions, was played on newly installed artificial turf. The old stadium turf was removed essentially for television, so remnants of white football lines weren't visible.
Canada has now won six straight against China.
Canada's best finish at the World Cup finish was fourth, in 2003. Its worst was 2011 when it came dead last, although the team rebounded to win Olympic bronze in London in 2012.
Canada was at the other end of a referee's call at the London Games in a heartbreaking extra-time loss to the U.S.
Saturday's win raised Canada's overall World Cup record to 5-11-3.
In the gaffe department, FIFA.com's matchtracker cited players' actions as "his" during the first half. It was fixed to "her," with a FIFA spokesman calling it a technical error.
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