"I have a protrusion in two discs in my lower back, which are causing me trouble that we're trying to address right now with a few days off," Rolen told MLB.com.
Rolen has not had an epidural injection and is trying to get pain relief from anti-inflammatory medication and rest. He missed a handful of games with back pain last month, including the entire Aug. 9-12 road series vs. the Cubs.
"Since my setback in Chicago, I've been uncomfortable and not able to perform and move offensively and defensively the way I hoped to have by this point," Rolen said.
Despite being hampered, the 37-year-old Rolen has batted .314 since the All-Star break and .323 in August. But in September, he is 1-for-10 and batting .244 with six homers and 33 RBIs overall this season.
"Hopefully it will subside and be better by the end of the weekend," Reds manager Dusty Baker said of Rolen's back.
Todd Frazier started his second straight game at third base in place of Rolen. Temporarily, Baker has a solution of where to play Frazier now that Joey Votto is off of the disabled list. Frazier was on a tear offensively while filling in for at first base the past six weeks, so there was anxiety over where he'd play when Votto returned.
"It always happens. Everyone wants you to tell them what happens next week," Baker said. "You can't do that. You don't know. You can never have enough pitching, can never have enough players and can never have enough anything without something. Something always works out, always. Sometimes you've got to let life run its course."