The Tigers signed catcher Robinzon Diaz, tweets Dejan Kovacevic of the Pittsburgh Post-Gazette. Diaz, 26, was released by the Pirates in November after hitting .279/.307/.357 in 138 plate appearances and catching 283 innings. He didn't hit much better in the minors this year. If the Tigers are happy with Diaz, they'll be able to retain him in future seasons since he's not close to six years service time.