But after surrendering the decisive two runs in the bottom of the seventh Friday, the bullpen's ERA rose to 1.00 in June, putting them out of reach to match the 1965 Orioles 'pen that compiled a 0.77 ERA in June.
They are, however, still on pace to beat the franchise-best 1992 Blue Jays' team, which had a 1.50 ERA in September.
Those statistics didn't matter to manager John Gibbons after the game, though.
"Like I said, they're not going to be perfect every time out there," he said.
Despite the loss, the bullpen has been a major reason for Toronto's midseason resurgence. The squad has won 15 of its last 21 games and has yet to lose a game when leading after seven innings.
The success can be traced back to the callups of Neil Wagner and Juan Perez on May 29. The pair has combined to give up just three earned runs over 27 2/3 innings since joining the club.
"We're strong down there," said Gibbons. "They've all been good, but the addition of Wagner really has helped -- especially at the time we put [Esmil] Rogers in the rotation. We had been looking for a right-hander who can get a tough right-hander out late in the game, and he's done that."
Michael Periatt is an associate reporter for MLB.com.