The silent contributor to the rise of receiver interference

In the wake of Willson Contreras’ brutal injury, receiver interference has found its place in the spotlight. Much of the talk has focused on the increase in catcher interference (and the accompanying injury risk) due to catchers moving closer to home plate in an attempt to frame low strikes. While an important factor, another cause for the increase in receiver interference calls is replay review.

The data

Receiver interference has become a reviewable play that teams can challenge in 2020, and it’s a call that teams must challenge for success. From 2020 to 2023, receiver interference challenges were successful 69% of the time, with a success rate about 10% higher than the next most successful replay category (forced plays).

Season	Total receiver interference	Receiver Interference Challenges	Challenges reversed
2018	41
2019	60
2020*	35	7	4
2021	61	17	11
2022	74	25	19
2023	96	21	14

From my experience: it’s a difficult decision to make.

In my personal experience umpiring amateur softball for 9 years, catcher interference can be a difficult decision to make. When the pitcher begins his windup, you make sure the pitch is legal, and once the pitch is released, you follow the ball to see if it ends up in the strike zone. If the batter begins to swing, you also need to determine whether or not the batter has swung. Dealing with this while tracking fast-moving objects and listening to sounds is tricky at the best of times.

Was the tone raised? The catcher will grab it and maybe block your view with his glove.

Did you hear two sounds in quick succession on the swing? Was it receiver interference or was it a bad tip?

Sometimes you get lucky and there’s an obvious decision, like if the batter drops the catcher’s glove, but it’s not always that simple.

Also consider the rarity of receiver interference. MLB employs 19 teams of 4 umpires, for a total of 76 full-time umpires (not counting call-ups). Even in 2022, there has been less than one receiver interference called by full-time referee all season. Typically, your first instinct when making a call will not be that receiver interference has occurred.

Diving deeper into the catcher’s interference challenges, they are often challenged by the batting team, and frequently they are challenged on infields. This is an important nuance, because a controlled swing will not make noise when hitting the catcher’s glove at maximum speed (hence the article title). Additionally, a controlled swing will not knock the glove from the catcher’s hand and is less likely to cause a painful reaction from the catcher. This limits the two key cues that tell officials that receiver interference has occurred.

A controlled swing will also further divide the referee’s concentration. Trying to determine if the pitch was in the zone, if the batter went around, and then if the bat made contact with the glove in a split second is very difficult.

For example

An example from April 27 of this year shows this perfectly as Cavan Biggio initially hits while checking his swing. Home plate umpire John Tumpane first calls a strike three, then follows up with a foul signal, before reuniting with the rest of his crew. Ultimately, the Blue Jays disputed catcher interference and the call was overturned.

MLB Branches

Diving into 2023, the most recent full season, there are two main takeaways. Of the 14 overturned receiver interference challenges, 12 of them resulted in receiver interference being awarded when it was not initially called. Of those 12 plays, 6 were plays where the batter attempted to slow his swing.

If receiver interference challenges did not exist in 2023, there would have only been 86 receiver interferences instead of 96, due to the 10 receiver interferences added after the challenges. This is still a strong increase compared to previous seasons.

However, applying the same logic to 2021 and 2022, catchers were hit with the bat at about the same rate as in 2019, but more were called catcher interference due to team challenges.

Catcher interference is definitely on the rise, and while some of that is due to catchers trying to steal more strikes, using technology to help umpires correctly make a difficult call (which the rebroadcast is supposed to do) contributes to this increase because Good.