TORONTO -- One of the standout qualities shown by the A’s in recent years has been impressive resilience in response to difficult situations. That characteristic will be sorely needed after what took place on Friday night.

It was building up to be an important series-opening victory for the A’s against a Blue Jays team that is on their heels in the American League Wild Card race. Backed by an outpouring of run support, Sean Manaea delivered a much-needed bounce-back performance by tossing seven innings of two-run ball with nine strikeouts.

Departing with a six-run lead, Manaea could only watch as the A’s bullpen squandered it away by allowing six runs in the eighth. A booming go-ahead two-run home run to left by Mark Canha that immediately put Oakland back ahead in the top of the ninth only led to more heartbreak in the bottom half. Sergio Romo allowed the first two batters to reach before surrendering a walk-off three-run blast to former A’s shortstop Marcus Semien in an 11-10 loss at Rogers Centre.

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The loss sunk the A’s further in their quest for the second AL Wild Card spot -- they are now three games behind Boston.

“You don’t have a choice but to respond,” A’s manager Bob Melvin said. “Just gotta come out and win a game tomorrow and erase that game. We’ve had some tough ones this year. You’re going to have those over the course of a season. I don’t know any [tougher game] than that.”

Three A’s relievers were called upon with the task of recording the final six outs. Between Romo, Lou Trivino and Yusmeiro Petit, the trio allowed nine runs while retiring only three batters. Petit, who has long been a reliable late-inning option for Melvin, took over for Trivino in a bases-loaded jam with two outs in the eighth and issued a walk before serving up a game-tying grand slam to Lourdes Gurriel Jr.

The A’s have adopted “Ride The Wave” as their team mantra for the 2021 season. Over the course of the final two innings on Friday, that wave evolved into a full-on roller coaster of highs and lows. It ultimately resulted in frustration. 

“It sucked,” Canha said. “We feel like we’re gonna win that game. An emotional game that’s back and forth and it didn’t work out in the end. 

“Sometimes you go in stretches like this where it becomes tough to win ballgames. That’s kind of what we’re dealing with right now.”

The A’s might officially have a bullpen issue on their hands. This meltdown was just the latest in what has been a string of rough outings for the relief corps. Wednesday night in Detroit, the bullpen inherited a three-run lead and ended up with a loss after allowing four runs in the final four innings. 

Even Thursday’s win came with some anxiety, as the A’s had to sweat out an 8-6 victory when the bullpen allowed Detroit back in the ballgame after inheriting a five-run lead following a solid start from Frankie Montas.

Given Manaea only had 86 pitches after seven innings, the inevitable question came Melvin’s way about why he did not allow the left-hander to go back out for the eighth, especially with the recent state of the bullpen.

“Fourth time through the lineup, I thought that was enough for Sean based on his workload,” Melvin said. “We just couldn’t finish it off. We should be able to hold an 8-2 lead. We just didn’t. Their bats got hot.”

If there is one positive to take away from a nightmarish evening for the A’s, it’s that Manaea appeared to find his groove again after enduring the worst month of his career.

"I was establishing my fastball. That was pretty big,” Manaea said. “I felt really good, and my tempo was a lot better than it has been recently.”

Over five starts in August, Manaea posted a 9.90 ERA and looked nothing like he did through the first four months of the season, when he bordered on All-Star worthiness as co-anchor of the staff alongside Chris Bassitt. Turns out, all he needed was for the calendar to flip to September.

Manaea entered the day with the highest sinker usage of any starting pitcher in the Majors, throwing it for 58.6 percent of his total pitch output. Against Toronto, he utilized the sinker heavily to keep hitters off-balance. Manaea threw the sinker for 64 of his 86 pitches and used it as the putaway pitch on eight of his nine strikeouts.

“I feel like when I can control [the sinker] and throw it to the other side of the plate, it’s really good,” Manaea said. “That’s always been key for me, to be able to throw it where I want.”

A return to form in September for Manaea shouldn’t come as a surprise, though. Historically, the final month is where he’s turned in his best work. The left-hander is now 10-3 with a 2.31 ERA (26 earned runs in 106 1/3 innings) over 18 career September starts.

For the A’s to reach their goal of a playoff berth for a fourth straight season, they could sure use this version of Manaea over the next few weeks.