Rob Brantly, 23, caught Tom Koehler in Miami's 4-2 loss on Wednesday night to the Pirates. And he's had history with Jacob Turner, stemming from when both were with the Tigers. Turner, Brantly and lefty prospect Brian Flynn were dealt to the Marlins from Detroit on July 23, 2012, for Anibal Sanchez and Omar Infante.
"The thing I'm worried about with Mathis is wearing him out, playing him too much," said Redmond, a former big league catcher who is well aware of the grind of the position. "Brantly is a guy who has had some good games. And he's had some games where everything has sort of snowballed on him.
"What I'm looking for from him is to eliminate those games where one thing happens bad, and here comes another, then another and another. It's eliminating that kind of snowball effect back there. Hopefully he's able to work on that and get better."
Brantly has started 56 games, and he's had his struggles in several areas.
"There are a few things he needs to continue to work on, like his game-calling," Redmond said. "He's had some tags at the plate that we've been working on. I think a lot of it just comes down to experience. This kid just hasn't caught many games."
Brantly has seven passed balls, compared to two for Mathis.
Mathis has thrown out 42.9 percent of the runners who have attempted to steal off him, compared to Brantly's 29.5 percent.
"That's a position where we really can't afford any injuries," Redmond said. "I know being a backup catcher as well. If they ran me out there too much, I might have gotten hurt. Or I did get hurt, and I played through it anyway.
"With Mathis, we've got to take care of him. As much as we all appreciate what he does, we have to take care of him too. I don't want to wear him out."