This time it was normally reliable shortstop Munenori Kawasaki, who committed a throwing error in the bottom of the ninth, which led to the Blue Jays' 2-1 loss against the Orioles on Monday night at Camden Yards.
"I was in a hurry and should have thrown the ball more cautiously," Kawasaki said through an interpreter at Kyodo News. "This is all my mistake."
Kawasaki fielded the ball cleanly, but bounced his throw to first base, and Edwin Encarnacion was unable to come up with the tough pick in the dirt.
Nick Markakis immediately made Kawasaki pay for the mistake. He sent an 0-2 fastball from Aaron Loup into left field to drive in the game-winning run as the Blue Jays lost for the third time in their past four contests, this time via a walk-off.
"He's a tough lefty," Markakis said of Loup. "I got to two strikes, I was in battle mode then, just looking for a pitch anywhere around the zone, don't try to over-swing, just put the ball in play. If it goes through the hole, it does. If I'm out, I'm out. I just wanted to give myself a chance to put the ball in play and it worked out."
Kawasaki was more than willing to assume responsibility for the loss, but manager John Gibbons was quick to defend his shortstop. It was an understandable reaction, considering Kawasaki has exceeded expectations since he was promoted from Triple-A Buffalo earlier this month.
The original plan was to use Kawasaki as a short-term replacement for the injured Jose Reyes until the Blue Jays could find another option from outside the organization. But that line of thinking changed when Kawasaki proved capable in the field, while also getting on base more than anticipated.
All of a sudden, Kawasaki became the primary option up the middle, and Gibbons wasn't about to turn his back on a player who spent the past two weeks earning high praise from within the organization.
"Let me tell you something, he has been playing his [butt] off," Gibbons told a group of reporters. "To hang that on him, wrong. You win as a team and you lose as a team. I'm not about to [blame him]."
Kawasaki doesn't possess a strong throwing arm, but has made up for it with a quick release and reliable accuracy. He hadn't made an error in 47 career games at shortstop entering Monday, but the timing of his first one couldn't have come at a worse time for the Blue Jays.
Loup was in a jam in the ninth inning of a tie ballgame with runners on first and second when he induced a ground ball, which should have resulted in the final out.
J.A. Happ gave the Blue Jays everything they could have hoped for during his fourth start of the season. Toronto's No. 5 starter allowed a hit to begin the game, but didn't surrender another until an infield single by Alexi Casilla in the fifth.
Happ retired 10 consecutive batters at one point and had little difficulty with a powerful Orioles lineup until the sixth inning. Baltimore opened that frame with a pair of singles, which almost resulted in outs as Brett Lawrie and Colby Rasmus just missed making spectacular diving catches.
Instead of a two-out, nobody-on situation, Baltimore had the makings of a rally, and both runners advanced when catcher J.P. Arencibia was unable to catch a fastball that bounced off his glove and to the backstop. Orioles first baseman Chris Davis followed with a sacrifice fly to score the only run against Happ, who struck out six over six-plus strong innings of work.
"We just crossed up, that's going to happen," Happ said of the pitch that got away from Arencibia. "But I stayed away from the big part of the barrel for the most part tonight, which is good.
"They got a couple of those hits to the other field, and then was a tough situation -- second and third with no outs -- but I was glad to get out of there with minimum damage, I guess."
Happ deserved a better fate, but took a no-decision after Chris Tillman matched him nearly pitch-for-pitch. Baltimore's right-hander allowed just one hit through six innings before Toronto put together a rally in the seventh.
With one on and two out, Arencibia fought off a tough two-strike pitch and snuck it through the right side of the infield to put Encarnacion in scoring position. Rasmus then came through with a two-strike single to right, tying the game at 1.
Tillman, who entered the game having allowed 11 runs in 14 innings this season, exited after Rasmus' at-bat. He was charged with one run on four hits, striking out three in what can easily be described as his best start of the year.
The focus after Monday's loss will likely be on the defense, but the offense struggled just as much. The Blue Jays have been held to three runs or less 12 times this year and have yet to find a consistent rhythm at the plate.
"Sooner or later, we'll start getting those balls to fall in, and it will be us doing that, getting that big run and stuff like that," Happ said. "You have to have confidence in that, trust that that's going to happen."