Jason Castro joins Chirinos as far and away the top two options still available in free agency this offseason. Castro has spent the last three seasons with the Twins and represents a slightly younger alternative to Chirinos. The knock though in the case of the Rangers is that Castro is a left-handed hitter which Texas already has plenty of at this point. However, at catcher, this concern is lessened because Castro and Trevino could split time revolving heavily around whether Texas is facing a lefty or righty on the mound that day.
Castro posted a 1.6 fWAR last season in 79 games and showed some impressive pop with 13 home runs. His .767 OPS isn’t quite to the level of Chirinos but it far exceeds what the Rangers saw last season. What Castro lacks in offense compared to Chirinos he makes up for with his glove finishing 26th among catchers in Fielding Runs Above Average last season at 3.5 according to Baseball Prospectus. Considering Jeff Mathis was brought in to be a defensive catcher and how poor his defensive metrics have actually been, Castro would be a massive upgrade on both sides of the ball. Castro also would be a better candidate for a multi-year deal if Texas believes he can form a solid tandem with Jose Trevino.