The middleweight from Wiarton, Ont., drew a first-round bye Friday, bringing her closer to the podium when Olympic women's boxing is contested for the first time at the London Games.
Spencer won't fight until Aug. 6, when she takes on either Brazil's Roseli Feitosa or China's Li Jinzi, two fighters she has beaten before. A victory will put her in the semifinals and guarantee her a shot at a medal.
"Mary has a bye in the first round and has already beaten both of the others. We had a pretty good draw. We are really happy," Canada's high-performance director Daniel Trepanier said.
"For sure, she has pressure but as a three-time world champion she knows a bit about pressure. She didn't know what to expect in coming here but she has been training well."
Custio Clayton of Dartmourth, N.S., will face Mexico's Molina Casillas on Sunday in the first round of the men's 69-kilogram event, while Simon Kean of Trois-Rivieres, Que., will fight France's Tony Yoka in the first round of the men's heavyweight 91-kilogram event.
"It is a really tough weight. But we are pretty happy with (Yoka)," Trepanier said. "He is young, but Simon can stop anybody. He feels good."
Meanwhile, the three Americans in the first Olympic women's boxing tournament have learned how fickle the draw can be.
While flyweight Marlen Esparza and middleweight Claressa Shields both drew first-round byes Friday, lightweight Queen Underwood was assigned one of the toughest paths to gold imaginable.
Underwood must fight British medal contender Natasha Jonas in front of her home crowd in the first round. The winner will meet Ireland's Katie Taylor, the top-ranked lightweight thought to be the best female boxer at the Olympics.
"She's going from one top person to the No. 1," U.S. assistant coach Gloria Peek told The Associated Press. "Queen can rise to the occasion, though. She has done it before, and she can do it again."
Taylor has beaten Underwood three times in previous meetings, but Peek sees no reason to be discouraged.
"When you have a difficult fight early, it just becomes more important that they're mentally ready right away," Peek said. "Any country can be beaten. We just have to make sure we're focused."
The rest of the 285 fighters in the field also learned their first-round fates during the long proceedings at ExCel, the multisport venue hosting the boxing tournaments. Most of the world's top-ranked fighters received byes, which means they won't begin until well into next week, but the draw's prime importance in amateur boxing was emphasized yet again — particularly for the women pioneers.
The five-day women's tournament features just 12 fighters in each of its three weight classes, which means a medal is within relatively easy reach. While Underwood faces a major challenge, Esparza and Shields must win just one bout to be guaranteed at least bronze. A gold medal is just three wins away.
"Cool. A step closer to my dream," the 17-year-old Shields tweeted.
American bantamweight Joseph Diaz Jr. is scheduled to meet Ukraine's Pavlo Ishchenko in the Olympics' first bout Saturday, and the Los Angeles-area native got a draw that could showcase his vibrant talent — or send him home early.
Diaz, who already has attracted interest from professional promoters, drew a difficult start against Ishchenko, the silver medallist at the AIBA European qualifying event earlier this year. The winner will face Cuba's top-ranked Lazaro Alvarez, the world champion.
"Just how I wanted it!" Diaz tweeted.
The Americans' two biggest boxers also face daunting challenges. Heavyweight Michael Hunter and super heavyweight Dominic Breazeale will face difficult Russian opponents in the first round, with a looming second-round matchup against the top seeds in two divisions that require just two wins to guarantee a podium finish.
"There were a couple (of draws) I would have liked to be a little different," Peek said. "We got some strong opponents for a couple of our boxers, but we've got some of the top fighters, too."
No eye-catching matchups immediately stood out in the men's draw — nothing compared to the first-round matchup in Beijing between featherweights Vasyl Lomachenko and Albert Selimov. Lomachenko's stylish victory over the Russian world champion set the Ukrainian on course for his first gold medal and the Val Barker Trophy as the Olympics' top boxer.
Lomachenko is back as the top-seeded lightweight in London, facing Colombia's Eduar Marriaga or Dominica's Wellington Arias in his debut in the second round Thursday. American lightweight Jose Ramirez, who nearly beat Lomachenko at last year's world championships, meets France's Rachid Azzedine in the first round Sunday.
Chinese light flyweight Zou Shiming must win just four fights to defend his gold medal from the Beijing Games after getting a first-round bye as the top-seeded fighter. Ireland's Paddy Barnes, another strong medal hopeful, also received an outstanding draw and a first-round bye.
Flyweight Rau'shee Warren, the first three-time Olympic boxer in U.S. history, got a first-round bye as a No. 3 seed. After losing his first bouts in Athens and Beijing, the Cincinnati native will get his third chance to win his first Olympic fight when he faces France's Nordine Oubaali or Afghanistan's Ajmal Faisal in the second round next Friday.
— With files from The Associated Press.