Zach Britton hasn't allowed an earned run in 43 straight games, but here are his closest calls

After another scoreless outing while closing out the Orioles' 4-3 victory against the Nationals on Monday night, striking out two more batters along the way, the sinker-hurling Zach Britton lowered his ERA to 0.53. If the season ended today, Britton would have broken the reliever's ERA record of 0.60 set by Fernando Rodney in 2012. 
But even that doesn't tell the full story -- Britton got his ERA that low by not allowing an earned run since April 30. (Though he did give up three unearned runs against the Padres on June 21.) Yes, that's crazy. Since last giving up an earned run, he's gone 41 1/3 innings, racked up 48 strikeouts and 14 walks -- and batters have a .383 OPS against him. 
That's 43 straight appearances without giving up an earned run -- a record since earned runs were recorded. 

Zach Britton (@Orioles) has gone 43 straight appearances w/out allowing an ER, longest streak of its kind since ER became official

— ESPN Stats & Info (@ESPNStatsInfo) August 23, 2016

That doesn't mean there weren't a few close calls along the way. Let's investigate 10 of those moments:
May 18: Mariners at Orioles
Entering with one out in the eighth inning, the Orioles' fireman quickly set about holding his team's 4-2 lead by leaving the bases stranded. 
But things got hairy again in the ninth inning. After Ketel Marte led off with a ground-ball double down the left-field line, Britton threw a wild pitch while trying to bury his sinker to Leonys Martin. With a runner at third and no outs, Britton struck out Martin with a gorgeous sinker on the inside corner, before getting two easy grounders back to the mound to end it. 
Even if the last one did see Britton bobble it before tossing to first. 

May 29: Indians at Orioles
The Indians got a rally going quickly as Marlon Byrd and Rajai Davis singled to start the ninth inning. Britton then induced what was first called a double play from Carlos Santana, but was reversed, leaving runners at the corners with only one out.
Leaning on the sinker that he throws over 90 percent of the time, Britton struck out Jason Kipnis and Francisco Lindor to end the inning. Despite knowing what was coming and where Britton was likely to toss it -- down in the zone -- Lindor couldn't help but take a hack. 

June 18: Blue Jays at Orioles
Britton started the final inning by striking out Kevin Pillar, but a single by Devon Travis -- followed by two walks to Darwin Barney and Russell Martin -- put Britton into perhaps the most difficult situation of his scoreless streak. Bases full, one out and the one-time viking and 2015 AL MVP Josh Donaldson at the plate. 
All Britton did: Induce a ground-ball double play to get out of the inning. 

June 21: Padres at Orioles
Ah, June 21. The day that Britton actually surrendered runs -- though they were unearned. Britton started off well, striking out Ryan Schimpf to begin the top of the ninth. But then, Derek Norris reached on a Ryan Flaherty error, and Christian Bethancourt followed with a single. Alexei Ramirez then singled in a run, and Travis Jankowski pulled an absolutely gorgeous squeeze bunt to second base to drive in another, sending Britton to the showers.

Later in the inning, Odrisamer Despaigne gave up an RBI single to Matt Kemp for the final run added to Britton's ledger. Except, ya know, they were all unearned, so not really. 
June 22: Padres at Orioles
One day after allowing those unearned runs, Britton was in trouble in the ninth again. After walking Brett Wallace and giving up a single to Bethancourt, Britton locked in. The southpaw struck out the next two batters to bring Jankowski to the plate. In a piece of poetic brilliance, the surfer-haired Padre hit a slow roller down the third-base line. While Flaherty's error the day before perhaps opened the floodgates to the Padres' run-scoring, on this day, he made a fine barehanded play to end the game. 

July 6: Orioles at Dodgers
Entering in the bottom of the 14th, the Dodgers threatened when an Adrián González double and a walk to Trayce Thompson put runners on first and second with one out. After Howie Kendrick grounded into a force out, Britton intentionally walked Yasmani Grandal to load the bases, so he could face his fellow reliever, Chris Hatcher.
Since Hatcher is a pitcher with all of 12 career at-bats, it's not surprising that Britton was able to get him to ground easily back to the mound. As seems to happen so often to pitchers whose job it is to throw strikes, he struggled a little with the toss to first, though. 

July 10: Angels at Orioles
The longest hit Britton's allowed this season was a 410-foot home run to Mookie Betts on April 11. Geovany Soto's 387-foot flyout was the second-longest. Given that this was little more than a lazy flyout that didn't quite make it to the warning track, it makes Britton's hot streak look even better. 

July 15: Orioles at Rays
After Brad Miller hit a one-out double, he advanced to third on a wild pitch. Britton then intentionally walked Evan Longoria to set up the double play. Turns out, he wouldn't need it. Two Ks swinging and the game was over, scoreless streak intact. 

Aug. 11: Orioles at Athletics 
Following a streak of 10 straight appearances -- totaling 8 1/3 IP -- in which Britton didn't give up a hit, the reliever found himself in some trouble against the A's. After a one-out walk and a two-out single, the powerful Khris Davis came to the plate. On a ground ball seemingly destined for center, Jonathan Schoop made a great play to get to the ball and prevent the runner from scoring. 

One batter later, Danny Valencia hit a much easier ball to the second baseman and Britton's streak was saved. 
Aug. 14: Orioles at Giants
With one out in the ninth, Trevor Brown singled, eventually moving to second on a fielder's choice. After intentionally walking Buster Posey, the count ran full to Denard Span. That would put the runners in motion and any slow roller or minor mistake could keep the inning alive. 
Fortunately for Britton and the streak, J.J. Hardy was just fast enough to beat Posey to second base. 

While it's hard to imagine Britton not allowing a run for the rest of the year, we're reaching the point where it's difficult to even remember what it's like when teams score against Britton. With the Orioles now two games back in the AL East, they'll hope that their late-inning savior keeps up his amazing season.