Why Red Sox fans shouldn't be concerned about Triston Casas being benched vs lefties

Triston Casas started 17 straight games after he returned from the 60-day injured list on Aug. 16. But in the past week, his name has been missing from the starting lineup three times.

Each time Casas was on the bench to start the game, Boston was facing a lefty starter. Casas entered two of the three games he didn't start as a pinch-hitter after the lefty was removed but didn't have much success as a stand-in.

It's no secret the first baseman has been in a slump — he broke out of a 3-for-32 skid on Sept. 10 with a laser of an RBI double against the Orioles, but he struck out in his three other at-bats of the night. As the Sox battle for a Wild Card slot, Casas may not be their best fit every night, not just because he's struggling lately, but because he's always had a hard time making contact against lefties.

Casas is slashing .222/.300/.400 against lefties this season compared to .250/.351/.440 against righties. His success at the plate is lower overall this year — mostly due to the four months he spent rehabbing his injured rib — but the discrepancy in his success rate against lefties and righties has improved slightly from last season. Casas slashed .215/.361/.456 against southpaws and .274/.368/.497 against right-handers in 2023.

Casas started off hot when he returned to action from the IL. He collected at least one hit in nine of his first 11 games back in the big leagues, including two homers and two doubles. It seemed like his many phantom swings over his months on the shelf paid off, but something has changed in his approach down the stretch.

Red Sox favor hot bats while Triston Casas struggles at the plate, particularly against lefties

Red Sox manager Alex Cora spoke with reporters about Casas' cold streak, and he believes the first baseman is overthinking his at-bats. That tracks, given Casas' reputation as a "cerebral-type of hitter," in his own words.

But before his return to the big league roster, Casas shared that he would be playing through pain. On Aug, 17, the day after he was activated, the first baseman said the pain was "minimal enough" to play through, but his rib may still be stinging him a bit. Throughout his recovery process, Casas emphasized the importance of rest, and his current struggles against southpaws give the Red Sox a chance to rest him and rely on hotter bats.

Whether the issue plaguing Casas' recent at-bats is overthinking, pain, or a bit of both, the Red Sox need to use their better offensive options during their Wild Card chase. Connor Wong and Romy González have played a solid first base in Casas' stead, and they're slashing .294/.369/.468 and .310/.377/.500, respectively, against lefties.

Casas showed that he can still hit, and do so with power, soon after his return a month ago. It's unfortunate that his offense has stalled at a crucial time for his team's playoff aspirations, but that's why Cora has benched him in favor of hotter hitters.

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