TORONTO — His team should not have been playing as Michael Saunders stepped to the plate in what became his biggest game north of the border since high school.

The Mariners were living on borrowed time, playing with house money and generally getting on the nerves of their Canadian hosts by somehow sticking around for the 10th inning of Friday's improbable affair. And then, Saunders saw a pitch he liked in that final at-bat and helped end this 9-5 win over the Toronto Blue Jays with a grand slam to right field.

Saunders had dreamed of moments like these while growing up in Victoria, B.C., and especially last winter, when his future with Seattle was becoming a longshot. But the center fielder, who helped start a tying comeback in the ninth with a solo home run, said the biggest memory he'll take away is that his teammates helped get him that final chance at a grand slam in the first place.

"It just goes to show the character of the team in this locker room right now," Saunders said after his team's fourth straight win. "It wasn't just a couple of hits. It was a full team game."

That's not just false modesty. Saunders would never have gotten to the plate against Toronto left-hander Luis Perez in the 10th without a series of unlikely events, along with several clutch performances.

The crowd of 24,303 fans at Rogers Centre saw two Canadian regulars make the night's biggest plays on opposite ends of the spectrum. Toronto was about to close out the game on a routine Kyle Seager grounder to third with two out and none on in a 5-4 game.

But somehow, Toronto third baseman Brett Lawrie — a B.C. native like Saunders and brother of former Washington softball star Danielle Lawrie — botched the throw to first base. From there, pinch-runner Munenori Kawasaki scrambled from first to third on an errant pickoff throw by catcher J.P. Arencibia.

The Blue Jays walked Dustin Ackley intentionally and then Mariners manager Eric Wedge sent seldom-used John Jaso to pinch-hit for Brendan Ryan. Jaso lined a two-strike single to center that tied the game.

"I'm just trying to get a base hit," Jaso said. "I'm not trying to do anything too difficult there."

The Mariners tried something difficult by waving Ackley all the way around from first when Toronto's outfielders took time picking the ball up. But Ackley was easily thrown out at home, sending it to extra innings, where singles by Justin Smoak, Jesus Montero and Alex Liddi loaded the bases with one out for Saunders in the 10th.

"It's good to see some of our young guys doing well and coming through in situations like that," Jaso said.

Montero had already hit a solo homer in the seventh inning to start the Mariners back from 3-1 down. Blake Beavan had fought to keep things close, but the Mariners didn't get their first hit off Toronto starter Rickey Romero until the sixth inning.

They only had a run at that stage because of two walks and an error by Lawrie in the third inning. But Montero homered in the seventh, Miguel Olivo singled and Casper Wells doubled to right center to tie it up again.

Eric Thames hit a solo homer for the Blue Jays off Tom Wilhelmsen in the eighth, and Toronto would later add an insurance marker to go up 5-3.

But the Mariners never quit.

"We played it really close to the vest, trying to keep it close in a tight ballgame on the road, when typically you probably wouldn't," said Wedge, whose bench was depleted by the 10th. "But we wanted to give our guys every opportunity to win that ballgame, and they really stepped up."

Wedge was impressed with the way Saunders had fought through at-bats earlier in the game without getting results. Then he gave the Mariners a glimmer of hope with his solo homer in the ninth off closer Francisco Cordero.

Perez had a streak of 12-2/3 scoreless innings before Saunders tagged him in the 10th. Saunders admitted he'd been "getting riled all game" by his fellow Canadians in the crowd.

"Maybe it's even worse, me being a West Coast Canadian, I don't know," he said. "But, then again, we had the last laugh."

Saunders added: "We know when we get nine guys swinging it ... we can hang with anybody. We'd lost four straight coming into this road trip, but kept our heads held high. We're playing good baseball and it's a long season."

Geoff Baker: 206-464-8286 or gbaker@seattletimes.com.