Let's talk about this for a second. What are the positive differences? Carroll hits about the same, is usually in the .650-.700 OPS range, and while generally more consistent than Casilla, is certainly not so much better that we think of him as much of an offensive upgrade. Then there's the defensive side. Casilla's got better range, isn't 93 years old, and makes the slick play. Give me a choice, and I think I might take Casilla. Alternate opinions welcome. Carroll has been a late-bloomer and with a bat in his hand, he has undoubtedly been better than Casilla. Carroll at 38 has been versatile and a good defender, not great. Casilla has played almost exclusively at second, where I believe he is the best middle infield defender the Twins have. Casilla will be 29 at midseason next year while Carroll will play 2013 at age 39. Casilla can be a threat on the bases, Carroll not so much. Carroll has never had a disabling injury, Casilla has spent at least four stints on the DL. If I had to pick one to start 140 games at second base in 2013, I would pick Casilla, but if the Twins are looking at those two as utility options, Carroll is the better choice despite his age.