The White Sox are signing outfielder Austin Slater to a major league deal, per a report from Jon Heyman of the New York Post. The terms of the agreement are not yet known. Slater will need to be added to the club’s 40-man roster when the deal is made official, though Chicago has space available so a corresponding move will not be necessary.
Slater, 31, was an eighth-round pick by San Francisco out of Stanford during the 2014 draft. The outfielder spent more than a decade in the Giants organization as he made his big league debut in 2017 and remained with the club through last season. In the first three seasons of his career, Slater was a decent but unspectacular fourth outfielder for San Francisco, slashing a combined .254/.335/.368 in 544 total plate appearances during that time. While primarily an outfielder, he also received occasional time at first base and even made token appearances at both second and third base off the Giants’ bench.
The outfielder broke out during the shortened 2020 season, however, with a 150 wRC+ and a .282/.408/.506 slash line in 104 trips to the plate while appearing in 31 of the club’s 60 games. That leap forward offensively earned Slater an expanded role over the next few years, and from 2021 to 2023 he became a regular for the Giants against left-handed pitching. While he was still generally shielded from righties, Slater slashed a respectable .257/.345/.412 in 343 games from 2021 to 2023. That’s good for a respectable 113 wRC+, and across those 838 plate appearances he walked at a 10.5% clip, swatted 24 homers, and swiped 29 bases despite frequent trips to the injured list cutting down on his playing time over the years.
Unfortunately for Slater, his production cratered in 2024. The outfielder hit just .209/.321/.266 (76 wRC+) overall in 212 trips to the plate this year while bouncing between the Giants, Reds, and Orioles. Even more surprisingly, the outfielder actually carried reverse splits this year after years of feasting on left-handed pitching. While he enjoyed a 141 wRC+ against lefties from 2020 to 2023, Slater hit just .188/.310/.231 against them in 142 plate appearances this year. Dismal as that overall production last year was, there is a silver lining in Slater’s performance. Once he arrived in Baltimore on the day of the trade deadline, he looked much more like the player he’s been throughout his career. In 79 plate appearances with the Orioles down the stretch, Slater hit .246/.342/.333 (102 wRC+) overall and posted a 114 wRC+ against southpaws.
That late-season rebound could inspire additional confidence in Slater’s ability to return to form in 2025 and beyond. That appears to be what the White Sox are betting on, and Slater makes plenty of sense for the club as a right-handed platoon option. Veteran lefty bat Andrew Benintendi is entrenched in left field, while the club also employs a host of left-handed youngsters in right field and at DH including Zach DeLoach, Dominic Fletcher, Gavin Sheets, and Oscar Colas. Of that group, only DeLoach (in a sample of just 79 big league PAs) lacks a significant platoon split.
Mixing in Slater against left-handed pitching should be a huge boost for a Sox offense that produced an MLB-worst 74 wRC+ against left-handed pitching last year, even if he merely recreates the production he offered the Orioles rather than bouncing back to the excellent form he showed from 2020 to 2023. While even an excellent short-side platoon bat isn’t going to make the White Sox contenders in 2025 following a 121-loss season this year, Slater was sufficiently attractive as a trade piece this summer to get dealt not once, but twice prior to the deadline. If he can garner that level of interest amid a down season, it’s easy to imagine the White Sox recouping some value for his services next July in the event he bounces back.