Horwitz (wrist) was cleared to begin hitting off a tee Sunday, Noah Hiles of the Pittsburgh Post-Gazette reports.
The 27-year-old is about a month removed from undergoing surgery on his right wrist and continues ramping up his hitting program. Horwitz was given an initial recovery timeline of 6-to-8 weeks and appears likely to be sidelined for Opening Day, but he may not miss much of the regular season.