Holmberg, who allowed six earned runs and seven hits with three home runs over 3 2/3 innings vs. Los Angeles for a 7-4 loss, is 0-3 with a 15.19 ERA in his last three starts. He is 1-4 with a 7.62 ERA in six starts.
If Holmberg is taken off of the assignment, Michael Lorenzen would likely be recalled up from Triple-A Louisville. Lorenzen started for the Bats on Saturday and delivered eight scoreless innings with one hit and has a 1.13 ERA in three starts since being demoted.
"The one thing we don't want to get away from is the fact that performance really drives this game," Price said. "The boundaries are a little looser with young players because you have to give them an opportunity, I feel, to pitch and struggle and work through struggles. But there's also an obligation to put our best team on the field. That's really where the debate will be here -- who our best five starters are for September and who is best equipped to go out there and give us a chance to win within the confines of some of the restraints we have with innings."
As some of the pitchers in the all-rookie rotation reach their innings limits next month -- such as Lorenzen or Raisel Iglesias -- there will be a need for reinforcements. Dylan Axelrod, who worked out of the big league bullpen as a long man until being sent down Aug. 19, started on Friday for Louisville. He could return to start when roster expand.
"At least a length guy [in the bullpen] -- one or the other," Price said. "He'd absolutely be a consideration to replace somebody that we're going to have to transition to the bullpen for innings limits."
• The Reds' No. 2 prospect, Robert Stephenson, came off of the disabled list on Thursday to start for Louisville and pitched four scoreless innings. Stephenson, who hadn't pitched since Aug. 12 because of a right forearm strain, gave up four hits and two walks with two strikeouts. He is under consideration for a September call-up next week.
Mark Sheldon is a reporter for MLB.com. Read his blog, Mark My Word, follow him on Twitter @m_sheldon and Facebook and listen to his podcast. This story was not subject to the approval of Major League Baseball or its clubs.