Seattle Mariners: Paul Sewald quietly setting MLB record

Paul Sewald has earned his place as the Seattle Mariners closer.

A mediocre reliever for most of his tenure with the Mets, Sewald put together a breakout campaign in 2021. He emerged as part of the Mariners’ committee of closers, notching 11 saves as he posted a 3.06 ERA and a 1.021 WHiP in his 64.2 innings, striking out an impressive 104 batters with 24 walks. He had been a bargain in free agency, a possible building block for the Seattle bullpen.

Seattle Mariners closer Paul Sewald setting records

He has continued that strong showing this year. Sewald has emerged as the Mariners’ primary closer, notching 19 saves while posting a 2.37 ERA and a 0.702 WHiP over his 57 innings, striking out 66 batters with 15 walks. Although his strikeout rate has decreased, Sewald has been even better this season than he was in 2021.

The key has been that no one has been able to actually hit Sewald. He has held the opposition to a .130/.204/.260 batting line over 212 plate appearances, allowing just seven homers. Opponents have a .150 batting average on balls in play, fueled by a meager 31.3% hard hit rate and an 85.8 MPH exit velocity.

His .150 BAbip is truly notable. Sewald currently has the record for the lowest BAbip in a season (since 1900) with a minimum of 50 innings pitches, eclipsing the .167 BAbip set by Vicente Romo back in 1968.

While there is a degree of luck involved in BAbip, Sewald has not just relied upon that fickle measure. He is an extreme fly ball pitcher, something that tends to result in a lower BAbip in the first place. His xERA of 2.20, and expected on base percentage against of .206, show how adept he has been at avoiding baserunners. His 81.3% strand rate is certainly good, but it is not close to Romo’s 87.3% strand rate in his 1968 campaign.

These are metrics that are not going to get a lot of attention normally. ERA, strikeouts, and saves generate attention because they are right there on the television and easily noted. It is fitting, however, that Sewald’s quietly dominant season is being fueled by such a metric – he is sliding under the radar despite having what could be a historic campaign.

Seattle Mariners closer Paul Sewald is having another fantastic season. This time, it is fueled by what could be a record setting batting average on balls in play against.