Montero played with the sore back in Cincinnati on Saturday and Sunday.
"We thought it was fine, but this weather is probably not helping things today," Maddon said of the chilly temperatures at Wrigley Field.
Montero said he felt fine when he woke up Tuesday but then went to lunch and his back tightened up as he was getting up from the table.
"It's nothing crazy," Montero said. "I don't want to irritate it again."
The Cubs expected to carry three catchers this season with Kyle Schwarber joining Montero and Ross, but Schwarber suffered a season-ending knee injury earlier this month. So, who is the Cubs' emergency catcher? First, Maddon said bullpen catcher Chad Noble, then picked Javier Baez, who has started at second, shortstop and third base this season.
"Javy can go back there in a heart beat," Maddon said.
Carrie Muskat has covered the Cubs since 1987, and for MLB.com since 2001. She writes a blog, Muskat Ramblings. You can follow her on Twitter @CarrieMuskat and listen to her podcast. This story was not subject to the approval of Major League Baseball or its clubs.