Not a free agent, but I'd look to make a trade for William Contreras of the Braves. He's hit real well in AAA but has had trouble in multiple tries in the majors. Seems like he's being passed over in the Braves organization - as Shae Langaliers is now their likely catcher of the future, and they extended d/Arnaud for 2 more years and signed Manny Pina to a 2/8 contract to be their backup. And the Braves are always looking for relievers. I know ideally you'd want a veteran to team with Adley, but Adley's so mature for a soon to be rookie, that going young with the #2 catcher might work out.