TORONTO -- If the Blue Jays shock the league and storm back in the AL Wild Card race, remember Friday night, remember Lourdes Gurriel Jr. and remember Marcus Semien. These are the moments that make a season.

Semien’s walk-off home run in the bottom of the ninth gave the Blue Jays their biggest, boldest, unlikeliest win of the season, an 11-10 victory over the A’s at Rogers Centre. The moment itself was brilliant, but it’s all the moments leading up to the crack of Semien’s bat that made it sound so loud.

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For two and a half hours, it looked like the Blue Jays were telling the truth about their dwindling postseason chances, shrinking under the weight of a better opponent at the worst possible time. Down 8-2 entering the eighth, the Blue Jays had been outclassed in every way, until suddenly they weren’t.

A two-out rally brought Toronto closer, setting up a game-tying grand slam off the bat of Gurriel. When the ball sailed over the wall and into the chaos, Gurriel began his 20-minute reign as the hero. Mark Canha put the A’s back out in front with a two-run homer in the top of the ninth, which looked like the final gut punch, but Semien refused to let it end that way.

“We just woke up,” said Semien.

That might be a warning.

Not only was this Semien’s 34th long ball of the season, setting a new career high, but it came against the team with whom he spent six years of his MLB career.

Entering Friday’s contest, there were 458 teams who entered the eighth inning trailing by six or more runs this season, and all but one had lost. Then, the Blue Jays became just the second team all year to overcome such an obstacle. This wasn’t supposed to happen.

Remove the emotion, and this win doesn’t do much. The Blue Jays are still five games back of the Red Sox for the second AL Wild Card spot and two games behind the A's, but the emotion matters here. Since their incredible return to Toronto a month ago and the 9-2 homestand that followed, Rogers Centre hasn’t been the same. It’s lacked energy, and of course it has. A team capable of being the most exciting club in baseball was playing quiet, predictable, middle-of-the-road baseball.

This win doesn’t happen without Gurriel, who Semien called one of the best clutch hitters in baseball, and it doesn’t happen without the half-dozen forgotten at-bats that led up to both home runs. It’s Semien, though, who was there at the end. The steadiest player in Toronto’s lineup all season long, this was who the Blue Jays wanted up in the biggest moment of their season.

“He’s our fearless leader,” said Alek Manoah, the rookie right-hander who allowed six runs over five innings. “He goes out there every day, and you can never tell if he’s 0-for-4 or 4-for-4. He just gives it his all. Tonight he was 0-for-4, and a lot of guys would be dragging their head and dragging their bat, but he went out there and won a ballgame. That tells you everything about his heart and his competitiveness. He wants to win and he never gives up on anything. When he goes, we go.”

It’s Semien who’s been the emotional balance of this team, too. On a roster overflowing with young personalities navigating the highs and lows of a Major League season, Semien is the straight face amid the mischief. That disappeared when Semien rounded third base, though, with his entire team already spilling onto the field and forming a runway for him to home plate. As the Blue Jays celebrated atop their logo, it seemed like they didn’t want to leave the field at all. The moment was too good to step away from.

“This guy is one of the hardest workers I’ve seen in my 35 years of baseball,” said manager Charlie Montoyo. “He does the same thing every day, the same preparation, takes ground balls, hits in the field, the same thing every day. Hard work pays off.”

From here, the Blue Jays still face a steep hill over their remaining 29 games. It will be more of a rock climb than a hike, but a win like Friday’s does more than just keep them afloat for one more day. Even some of Toronto’s wins in recent weeks have come without momentum, but by beating the A’s in this specific fashion, the Blue Jays can finally hold up their trademark win of the 2021 season.

If there’s ever going to be a win that’s the start of something, it’s this one.

“Every win is so important right now,” Semien said. “Just to be able to swing the bat and give us the win right there, it’s huge. The biggest at-bat of the year for me, obviously. I hope we can just build off this, score some more runs tomorrow and see what happens.”