Mercer has had one run-in with St. Louis right-hander Lance Lynn, and the small sample size of his 2-for-3 with a two-run double got him the nod over Barmes, who himself has done well against Lynn (6-for-23, with two doubles, a homer and five RBIs).
"Yeah, Jordy has some at-bats against Lynn, and we tried to get maybe another little offensive bat in the lineup," Hurdle said. "So that's the reason for it."
Maybe that won't be the only spike in the Bucs' batting order: Gerrit Cole, the day's starting pitcher, took a .206 average with five RBIs into the game.
Tom Singer is a reporter for MLB.com and writes an MLBlog Change for a Nickel. He can also be found on Twitter @Tom_Singer. This story was not subject to the approval of Major League Baseball or its clubs.