PHILADELPHIA — Disbelief persisted on Tuesday at Citizens Bank Park, one day after the Red Sox suffered an unprecedented walkoff loss to the Phillies.
To recap: With the bases loaded in the bottom of the 10th inning on Monday night, Phillies infielder Edmundo Sosa took a pitch that was ruled a ball. But Sosa immediately suggested after the checked swing that his bat had nicked the glove of Sox catcher Carlos Narváez.
Video review clearly showed that Sosa’s bat — even though he didn’t swing — had indeed brushed the catcher’s mitt, resulting in a catcher’s interference call that resulted in Sosa being awarded first base and a run being forced home for a 3-2 Phillies win.
“It was a [expletive] way to end a great baseball game,” said Sox manager Alex Cora. “[But] that’s the rule.”
It marked just the second known instance in baseball history that a catcher’s interference call delivered a walkoff, with the other coming when Hall of Famer Johnny Bench was flagged for the infraction in a Reds-Dodgers game on August 1, 1971.
“The only good thing about it is, I’ve got something in common with Johnny Bench,” said Narváez. “But you don’t want to lose a game that way.”
Remarkably, the first inning on Tuesday featured another run-scoring catcher’s interference call — this time when Narváez stepped in front of the plate as Bryce Harper attempted a steal of home. But while that rarity (“This is the first time I’ve ever seen it on the field,” said umpiring crew chief Quinn Wolcott) represented a one-off, the sort of bat-mitt interactions seen on Monday night are becoming far more common.
From 2000-09, there were an average of fewer than 20 catcher’s interference calls per season in baseball. In the 2002 season, there were just nine such calls all year.
But the numbers started to rise in the 2010s, averaging 42 per season from 2016-18 (more than double the first decade of the 21st century), then exploding in recent years. MLB set records in both 2023 (96) and 2024 (100) for catcher’s interference calls. Through Monday, there had been 55 such calls this year — on pace for more than 90 for a third straight year.
Narváez leads MLB with five catcher’s interference calls this year. The Sox lead the big leagues with eight (including one on which Connor Wong suffered a broken pinkie).
Why is this happening? It’s not random.
“There’s obviously an inherent risk with [a catcher] being closer to the hitter, but depending on who you ask, there might be a tradeoff that we think is worth it,” Red Sox catching coach Parker Guinn said cryptically.
The primary benefit of both setting up and receiving the ball closer to the hitter — even at greater risk of a catcher’s interference call — is pitch framing.
It wasn’t lost on the Red Sox that the Yankees regularly were and are close to or at the top of the big leagues in catcher interference — or that their backstops regularly have elite framing numbers. Jose Trevino won a Gold Glove for the Yankees in 2022. The Sox realized that he was setting up about six to eight inches closer to hitters than their catchers.
Their catchers started moving closer to the batter in recent years. Narváez — who, like Guinn, came to the Sox this year from the Yankees — was comfortable doing so.
“The main goal on [receiving the ball closer to the plate] is trying to be closer to a hitter to rip everything in the bottom of the zone, trying to keep strikes strikes, and gain some pitches at the bottom of the zone,” said Narváez. “I just want to gain every pitch possible for my pitcher.”
Red Sox game planning and run prevention coach Jason Varitek — who was called for catcher’s interference just five times in a 15-year big league career — added that proximity to the plate also benefits catchers’ efforts to claim strikes on the outer edges of the plate.
“The closer you are to the hitter, the less the ball sprays. The closer the umpire is to the plate, the ball has less room to move east and west,” said Varitek.
Catcher positioning has changed in recent years because of technological advances. The increased precision offered by an array of video camera positions from Trackman and then Hawk-Eye systems employed by Statcast as well as biomechanical tracking technologies that have emerged in the last decade demonstrated more precisely where players are positioned — and both the risks and payoffs of that positioning.
Catchers have always paid attention to a hitter’s position in the box to figure out where they should set up, but the exactness with which they study the matter has changed. In recent years, Varitek and Mike Brenly (formerly a bullpen catcher, and now in charge of replay review) had broken down video of batter position and swings to determine whether Sox catchers should set up in a standard position, or move either closer to or further from the hitter to limit catcher’s interference while reducing the distance to the plate.
More recently, the process has become automated based on biomechanical data. The Sox know exactly where hitters stand in the box and how long their swings are – both early in at-bats and in two-strike counts. Where a catcher should set up for each hitter is discussed in pre-game meetings, and information about setup depth is also included inside catcher’s wristbands.
“We have enough measurements and things to allow us to know who’s where, when and how,” said Varitek.
That said, there are known risks with receiving the ball closer to the batter. The most significant is the possibility of injury — as when Wong was struck by George Springer (known for the length of his swing — and thus a player for whom catchers set up deeper than others) this year or when Willson Contreras suffered a broken forearm in 2024.
“You can’t just say closer is better,” said Varitek. “We can’t tell somebody to do something without giving them boundaries and/or precautions and/or parameters to work with.”
The other, of course, is catcher’s interference. The Sox are on pace to surpass the big league record of nine such calls in a single season. Is that a price worth paying for the work Narváez does with the pitchers?
“We think so. He’s arguably the best catcher in baseball defensively,” Guinn said of Narváez, who ranks third among catchers with 11 Outs Above Average (as assessed by Statcast).
Still, as much as Narváez loves to get strikes for his batterymates, he felt chastened by the game-ending catcher’s interference call — even if it did put him in company with Bench.
“I don’t want to be remembered for that,” he said. “It’s a valuable learning moment for me.”
Alex Speier can be reached at alex.speier@globe.com. Follow him @alexspeier.