White Sox Shut Down Gregory Santos: A Season In Review

On Wednesday the White Sox shut down reliever Gregory Santos for the season. 

Santos was placed on the 15-day IL with right elbow inflammation but manager Pedro Grifol says the decision to shut him down was a precautionary measure. 

“He’s had a good year. We’re just erring on the side of caution and shut him down for the rest of the year to let doctors evaluate him,” Grifol told reporters. 

Santos began the year as a relatively unknown pitcher. Former general manager, Rick Hahn, picked him up off the scrap heap during the offseason. Santos was previously the San Fransico Giants 25th ranked prospect. The hard-throwing right-hander was designated for assignment before the start of the season when the White Sox decided to take a flier on him. 

This year, he was excellent out of the bullpen, emerging as one of Grifol’s favorite high-leverage options late in games. Santos posted a 3.39 ERA in 66.1 innings of work. Santos racked up five saves when the White Sox asked him to make a few appearances as a closer.

His command was a concern when he first arrived with the White Sox, but the San Cristobal native racked up 66 strikeouts and just 17 walks. His 5.9% walk rate was by far the lowest of his young career. Santos also ranked inside the top ten percent of MLB pitchers in expected slugging percentage (.311), XWOBA(.274), and xERA (3.10). 

His biggest change from a year ago was his increased use of his sinker. Santos was mainly a two-pitch pitcher in 2023, throwing his slider 52.6% of the time and his sinker 43.8%. His sinker averaged 98.8 mph and paired nicely 91 mph slider. Last season he used his sinker in just 10.4% of his pitches, albeit in a small sample size. 

Opponents hit just .198 against his slider, which also generated a 37.5% whiff rate. Santos' slider generated a run value of 17 which made it by far his most effective pitch. 

He also added a changeup to his arsenal but only threw it 15 times. It will be interesting to see if that is something he continues to develop during the offseason. 

He struggled in his final appearance of the season, giving up three runs in the eighth inning against the Nationals. However, before that, he had gone six consecutive appearances without allowing a run. 

It is hard to view Santos's season as anything but a success. Before the start of the season, it was unclear if he would even make the team. By season’s end, he was by far the White Sox most effective weapon out of the bullpen. 

Santos only had one year of control and will enter Pre-Arbitration during the offseason since he doesn’t have three years of service time under his belt. He will likely see a pay raise if the White Sox bring him back.