Thinking about the way in which the Twins will likely set up their Opening Day lineup (I took a stab here), the left side of the field could be a massive black hole. At third base, Miguel Sano is all but certain to get the majority of the time. Shortstop is going to be manned by Jorge Polanco after the Twins held onto Brian Dozier, and left field is likely to be played by a combination of Robbie Grossman and Eddie Rosario.
Looking at that group as a whole, they combined to be worth -31 defensive runs saved (of which Grossman accounted for -21). At third, Sano has found a tough time staying within himself. His range is acceptable enough to play the role, but he often finds his feet unsettled, throws rushed, and has displayed errant accuracy far too often when throwing across the diamond. Polanco has never been expected to have the arm strength to stick at short, and the last time he regularly played the role prior to last season was at Double-A in 2015.
In the outfield, Eddie Rosario went from an assist machine to replacement level. Assists being a fickle measure, teams simply stopped running on him a year ago. He backed up his 12 assists in 2015 with just four in 2016, all while going from 10 DRS to zero. The speed is there, but whether or not he's all in and committed on a nightly basis remains to be seen, and has been a knock throughout his career. Grossman totaled a defensive season in left that would make Delmon Young and Josh Willingham blush. He's been right around league average previously, but he'll have to prove the massive cliff he fell off in 2016 was simply a misstep.
Although the Twins didn't do much this offseason to elevate themselves through the free agent market, part of the draw behind Jason Castro was his pitch framing skills. The idea is the with him behind the plate, Minnesota's pitching woes would be somewhat addressed. The reality is that if the entire left side of the field struggles to help out, it's going to end up as a net loss anyways.
The Twins 5.39 ERA among starters a season ago was worst in the big leagues. What's worth noting though is the 4.82 FIP they posted (although still not good coming in at 28th) is virtually a half a run shy of what the actual results were. On the relief side of the equation, things weren't too different. Minnesota relievers owned a 4.63 ERA but posted a 4.18 FIP. Boiling it down to the Twins playing bad defense last year is a pretty easy suggestion, but also one that's widely known.
What 2017 presents as a question is whether or not things will get better. Byron Buxton sticking in the MLB outfield for the whole season should help guys on both sides of him. If the Twins don't develop the left side of the diamond though, they'll have a glaring deficiency for opposing teams to exploit. It's going to be something worth watching, and a development that I'd guess Twins pitchers have a close eye on as well.
