Mateo isn't in Baltimore's lineup for Friday's game against the White Sox, Roch Kubatko of MASNSports.com reports.
After going 3-for-13 with three RBI and two steals in the Orioles' last series against Oakland, Mateo will get an off day in Friday's series opener with Chicago. In his absence, Gunnar Henderson will start at shortstop, Anthony Santander (back) will serve as DH and Terrin Vavra will get a start in right field.