Arenado is out of the lineup for Thursday's game against the Reds, Patrick Saunders of the Denver Post reports.
Arenado will get a rare day off for the first time since June 11. The All-Star has been swinging the bat well all year, and is hitting .308/.364/.359 over the course of the last 10 games. He will likely be back in the lineup for the series opener against the White Sox on Friday.