"The guy who came in could have done a better job," Flowers said. "The next guy up needs to make sure there's no dropoff. You can't say, 'Well, I haven't had a lot of reps,' as an excuse."
When asked if Marcus Hutchins - who was Perkins' replacement - should have been ready considering he started all of last season at left tackle, Flowers said, "Yeah, I could say he should be ready, but he wasn't."
Flowers said the offensive line can't afford to take a step back if Perkins is out for a while.
"Coming off last season and how we played then compared to how we're playing now - we can not go back to that," Flowers said.
"That's what killed us last year - the way the O-line played. There weren't running lanes, and we weren't able to protect the quarterback. We can't go back to that."
Added RB Johnathan Gray on if there was a noticeable change offensively when Perkins went down:
"It didn't change any plays being called, but it definitely hurt us. Hopefully, we get him (Perkins) back soon."
Hutchins is expected to start at right tackle against TCU, although Elijah Rodriguez will get a look at RT in practice this week, we're told.