Like most players, Montero likes bats that have the grain that sticks out a little bit rather than feel completely smooth.
"If you hit it right, you've got a better chance to get a better spin on the ball," Montero said of a bat with the grain sticking up.
So why didn't he just feel the grain with his hands?
"I had my batting gloves on, and with the batting gloves on, I couldn't really feel the grain of the bat," Montero said. "It takes a lot of work to take my batting gloves off after I hit, because I put so much sticky stuff on my batting gloves."
So in order to pick out a new bat and get up to the plate quickly, Montero used his mouth to feel the difference in the grain.
"I actually wasn't licking it," he said. "It was more my teeth, so kind of feeling the [grain]."
Steve Gilbert is a reporter for MLB.com. Read his blog, Inside the D-backs, and follow him on Twitter @SteveGilbertMLB. This story was not subject to the approval of Major League Baseball or its clubs.