TORONTO -- What was shaping up as one of the most inspiring wins of the season for the Red Sox on Tuesday night at Rogers Centre instead turned into one of their most deflating defeats.

When an early 4-1 deficit turned into a late 5-4 lead and ultimately a 6-5 loss to the Blue Jays, Boston’s record against American League East opponents slipped to 7-16 this season.

This one unraveled swiftly in the bottom of the ninth, as the Red Sox had no answers without closer Tanner Houck, who is on the restricted list for this series in Toronto because he isn’t vaccinated against COVID-19. All four Blue Jays who batted in the ninth reached base, capped by a walk-off single by Vladimir Guerrero Jr.

“I mean, we go with the 26 that are here,” said Red Sox manager Alex Cora. “And we tried to get 27 outs and we didn’t do it.”

Tyler Danish fired a 1-2-3 eighth inning and Cora entrusted the righty to go for his first career save in the ninth.

Danish gave up a single to Alejandro Kirk and walked George Springer. Hansel Robles was next to get a chance and Bo Bichette greeted him with a first-pitch, game-tying single. Guerrero ended it by hammering a 2-0 slider onto a patch of grass in left.

“Just things went their way with two ground balls. Easily could have been double plays, but that’s it,” said Robles after his fifth blown save in seven opportunities this season.

Danish felt bad that Robles was left to take him off the hook.

“We’re down a guy, but that means everyone else has to step up,” said Danish. “That opportunity [was with] me and I didn’t come through. You want the ball in those situations in the ninth, I just didn’t get the job done. This one’s on me.”

Boston’s hottest reliever of late is John Schreiber (0.76 ERA), who he needed just 11 pitches to get through the seventh.

Did Cora think of bringing the righty back out for the eighth?

“I mean, we’ve got a game [Wednesday] and he’s our best reliever,” Cora said. “T.D. did a good job. It was a bunch of righties and he’s got good stuff. We’re trying to get 27 there and we didn’t finish it. I mean, that’s the way I saw it. That’s the way I managed the game. I’m the manager here and I decided to go with [Danish] for two innings.”

If not for the ninth-inning malfunction, this would have been Rob Refsnyder’s night.

The veteran journeyman has done a tremendous job for the Red Sox (.368/.444/.632 line in 45 plate appearances) and he clocked a game-tying, two-run homer to center in the seventh.

The last two nights, Refsnyder stepped in as the leadoff hitter and center fielder in place of Jarren Duran, who is also on the restricted list due to not being vaccinated.

“I was fortunate to get a fastball out over the plate,” said Refsnyder. “He has a really good slider. It’s a good moment to tie the game and then [Christian Vázquez] with the big hit to put us one run ahead. Unfortunately it wasn’t enough. That’s a really, really good team and they’re good at home.”

The Red Sox, who came into this series on a 19-4 tear in June, were hoping to establish some momentum against a division foe after playing almost exclusively outside of the division since the beginning of May.

Instead, it has gone the other way. Cora and his team will try to stem the tide by salvaging Wednesday night’s finale behind Nick Pivetta, their hottest pitcher.

Unless Pivetta can pitch his second complete game of the season, the Sox will have to piece it together once more without Houck, who will re-join the club at Wrigley Field for a three-game series against the Cubs that starts Friday.

“I mean, he's a stud pitcher,” said Red Sox righty Michael Wacha. “But we knew what we were going into coming here. This is what it is.”