At times it has been one step forward, two steps back in her return from anterior cruciate ligament surgery. The 31-year-old has had some missteps at the tournament. But the resilient Sesselmann has bounced back and continues to line up alongside teenage centre back Kadeisha Buchanan in a stingy Canadian defence.
In the tournament opener against China, a giveaway during a passage of erratic play in the first half meant Sesselmann had to convince coach John Herdman to keep her on the field. There were also some hiccups in the round-of-16-game against Switzerland.
Herdman has defended his centre back. But Sesselmann has felt the heat from the media, perhaps unfairly for an athlete who has had to go from zero to a 100 in returning from a serious knee injury at the sport's biggest showcase.
"You hear it here and there," she said of the criticism. "People are always going to have something to say. You can be the best player in the world and they still have something to say. I'm not even worrying about that. I look where I am and how far we've gotten at the tournament and it's kind of that moment where you're just like 'We're here, you're not.'
"This is our team and we're focused on the talk at hand ... People can say what they want but we're focused on winning the Cup."
Canada's next challenge is England on Saturday in the quarter-finals at B.C. Place Stadium.
Sesselmann tries to see the bigger picture when it comes to being under the spotlight.
"Everybody in this tournament makes mistakes. Even the greatest athlete in the world makes mistakes," she said. "It's part of the game.
"It's how you bounce back from them. And each game for me has been better and better. My job is to defend and that's exactly what I've been doing."
Canada is tied with the U.S. and Brazil with just one goal conceded at the tournament.
"I think people fail to realize we're doing that part of the job very well so they just focus on the negatives," Sesselmann said. "For me, I'm not focusing on that at all.
"I'm focusing on what my job is and I'm pretty happy with what we've been doing."
Sesselmann, who as a left-footed player complements Buchanan on the right, says she has been feeling calmer each time out. And she takes great pride in having made it back to the national team.
"This time last year was a really bad time for me," she said. "And the whole (recovery) process itself, there were tons of highs and lows — mostly lows. So it was a really difficult passage for me ... For me, I look where I was over a year ago, I'm just so proud of myself and just really excited."
"To be here is the greatest thing ever."
The American-born Sesselmann qualifies to play for Canada through her father, who was born in Stephenville, N.L. She was 28 when she made her debut for Canada.
She has won 44 caps for Canada and started all six games at the London Olympics where the Canadian women won bronze.
Sesselmann ripped up her knee in practice before last year's Cyprus Cup, acknowledging "my dreams were slowly fading away.'' Sick the first three months of a rough recovery, she dealt with plenty of pain and spent time in hospital.
While she is back playing, she acknowledges there is more to do.
"I still have some strength I need to get back, so I'm working on that," she said.
Off the pitch, Sesselmann has her own successful fitness DVD program called "Fit As a Pro,'' which focuses on quick, high-intensity on-the-go workouts.
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