Peralta (back) won't travel with the Yankees on Monday for the final series of the regular season at Texas, Bryan Hoch of MLB.com reports.
The 31-year-old will continue his rehab at Somerset and could throw a live bullpen session this week. Peralta has been a key bullpen piece with a 2.72 ERA in 56 appearances for New York this year, and it appears he could be available for the start of the ALDS, which begins Oct. 11.