Entering Wednesday's game, the D-backs' rotation had the worst ERA in the Majors at 7.82, nearly two runs worse than the 29th-ranked Twins.
"I know it grinds on him," D-backs manager Kirk Gibson said of Montero. "Catchers take it personally."
Gibson added that Montero has been a vocal encourager of the pitchers -- as well as the entire team -- during games.
"One thing is for sure, I've got their backs," Montero said of the rotation. "I'm going to keep working to help them get better."
Steve Gilbert is a reporter for MLB.com. Read his blog, Inside the D-backs, and follow him on Twitter @dbackswriter. This story was not subject to the approval of Major League Baseball or its clubs.