TORONTO -- The Blue Jays' bullpen has become a pretty big strength during the second half of the season, but it could be headed for a breaking point with just four games remaining in the regular season.
Toronto's relievers have been left battered and bruised over the last week. Joaquin Benoit might miss the rest of the season with a torn left calf muscle. Roberto Osuna has blown each of his last two save opportunities, and Jason Grilli has seen his ERA rise from 3.02 to 4.01 in less than a month.
The latest blow came on Wednesday night, when Osuna surrendered a go-ahead homer to pinch-hitter Hyun Soo Kim in the top of the ninth inning. The two-run drive sent the Blue Jays to a 3-2 loss and ensured the club would have to wait at least a couple of more days to clinch an American League Wild Card spot.
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"I think we're going to be fine," Osuna said through an interpreter. "We're playing against the best teams in the Major Leagues right now, in our division. Stuff like today, it's supposed to happen sometimes, but I'm not worried at all. I think we're going to be in a good position after the next four games."

Toronto's bullpen was a major issue during the first two months of the season, but Grilli helped stabilize the relief corps upon being acquired from Atlanta at the end of May. Benoit had a similar impact in July, and the two combined with Osuna to form a strong trio at the back end of the Blue Jays' bullpen.
The problem is that one of those relievers has been completely eliminated from the equation, while the other two are struggling at the wrong time. After surrendering Mark Trumbo's Major League-leading 46th home run to begin Baltimore's comeback, Grilli has surrendered five runs over his last inning of work. Osuna experienced a slight drop in velocity on Tuesday and, to a lesser extent, Wednesday. Overall, Toronto has blown three ninth-inning leads over its last four games.

"It's tiring; everybody's tired," Grilli admitted. "We're all on an even playing field that way. I've been doing this since before Spring Training. There's a lot that goes into this. This is the time when it's the hardest to dig down deep. You go on pure adrenaline, pure guts. You try to give your all, and that's what's happening. We're doing that. The effort hasn't changed."
The issue Toronto currently faces with its bullpen is a lack of options. Left-hander Brett Cecil, who got the Blue Jays out of a bases-loaded jam in the seventh inning on Wednesday, will continue to see an increased role, but the workload of Joe Biagini has to be monitored as he nears the end of his first full season in the big leagues.

The biggest help of all could come from the starting rotation. Marcus Stroman appears to be the logical pitcher to transition to a relief role if the team qualifies for the postseason, while rotation spots would go to Aaron Sanchez, J.A. Happ, Marco Estrada and Francisco Liriano.
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A closer in college, Stroman has done the job before, but that move had better work alongside quick turnarounds from Grilli and Osuna. Otherwise, Toronto could be asking for trouble over the next week.
"I've told you guys all along, since I've been with this group, that's what they do: They've been resilient," Blue Jays manager John Gibbons said of his team. "It's two good teams battling, and it came down to the ending. They got the big home run there. It's two teams with a lot at stake. They came up with the big blow."