Baseball boils down, at it's most fundamental level, to three aspects: pitching, hitting, and fielding. Analyzing the statistics behind pitchers and hitters continues to improve, but defensive stats are seemingly still in a somewhat primitive limbo. The league, with the advent of Statcast, looks to be on the cusp of having some really good defensive statistics to sink your teeth into. With that being said, analyzing defense in 2016 isn't a refined art, so we'll have to make do with what we have.
Catcher: Sandy Leon v. Roberto Perez
If Yan Gomes hadn't been injured this season, he most likely would still be the starting catcher despite his horrendous season at the plate. With Gomes being the second string at this point, Roberto Perez has stepped in and taken over as a decent starting catcher. Opposite Perez is catcher Sandy Leon, who is having a monster breakout season after a disappointing 2015. Leon, who logged over 600 innings behind the plate in 2016, has a fantastic 41% caught stealing rate, yet it still doesn't match Perez's video game-like 50%. Perez has a slight edge over Leon in terms of Defensive Runs Saved (5 compared to 3), but Leon beats out Perez in overall defensive rating (8.1 to 6.9). If offense was being accounted for, Leon is the clear choice; when looking at defense, it's a bit of a toss-up. Advantage: Sandy Leon (but only slightly)
First Base: Hanley Ramirez v. Mike Napoli
Whew buddy, this is not fun. First base is not a defensive strength for either team. 32 year old Hanley Ramirez and 34 year old Mike Napoli have both been equally terrible at fielding their position this season. Napoli has been slightly worse in terms of DRS (-4 compared to -5), but he's been markedly worse when looking at UZR/150 (-6.1 compared to -4.9). Both men are slow on their feet and don't have great range, so a good strategy for both sides may be to hit it to first base and hope it gets through. Hanley Ramirez has a horrendous overall defensive rating (-13.4), and Mike Napoli doesn't fare much better (-11.8). Advantage: Mike Napoli (but no one really wins in this scenario).
Second Base: Dustin Pedroia v. Jason Kipnis
While Jason Kipnis has shown a lot of improvement at fielding his position, Dustin Pedroia remains one of the best defensive second basemen in the game, and arguably the best defensive second baseman in the American League. Despite his short stature, Pedroia leads the AL among second basemen in UZR/150 (13.1), DRS (12), and overall defensive rating (14.0). Kip has put himself into the conversation by being in the top 4 in all three of those categories, but Pedroia is still the better defender. Advantage: Dustin Pedroia.
Third Base: Travis Shaw v. Jose Ramirez
The Angry Hamster has had an incredible season, filling in nicely for Michael Brantley offensively and finding a permanent home at third base with the departure of Juan Uribe. Travis Shaw, while having a down year offensively, is still playing a decent third base for the Red Sox. Shaw has been miles ahead of Ramirez in terms of DRS (10 to -1), but Ramirez has been better in terms of UZR/150 (4.0 to 1.6) as well as overall defensive rating (3.7 to 2.6). Depending on how you weigh each stat, an argument could be made for either player. Advantage: Draw.
Short Stop: Xander Bogaerts v. Francisco Lindor
Glorious. Absolutely glorious. Bogaerts is one of the best young shortstops in baseball, and he has a fantastic career ahead of him both at the plate and in the field. Unfortunately, he is facing off against the best young shortstop in baseball, Francisco Lindor. Any way you slice it, Lindor is a defensive wizard. Whether it's his incredible DRS (17), his impeccable UZR/150 (21.3), or his brilliant defensive rating (27.8), Francisco Lindor wins easily and it's really no contest. Advantage: Francisco Lindor every day of the week.
BONUS: Look at how awesome Francisco Lindor is:
Outfield: Mookie Betts, Jackie Bradley Jr., and Brock Holt v. Rajai Davis, Tyler Naquin, and Lonnie Chisenhall
...yikes. This is painful. It's actually more painful than the defense at first base because at least when looking at first base, the Red Sox are also terrible defensively. Here, the Boston outfield runs circles around the Cleveland outfield. Rajai Davis is fairly comparable to Brock Holt in that neither are very good, but the duo of Betts and JBJ absolutely decimate Naquin and Chisenhall. For Cleveland, Davis is the only defender with a positive defensive rating (3.9); Lonnie Chisenhall is bad (-4.7) and Tyler Naquin is horrendous (-12.6). On the other hand, Boston has two outfielders, Mookie Betts and Jackie Bradley Jr., with great defensive ratings (16.9 and 5.6, respectively) and one with an awful rating (Brock Holt with a -18.3). Mookie Betts specifically, in terms of DRS, is the best in the American League with a DRS of 32. Don't be surprised if, over the course of the ALDS, some hits are robbed by the Boston outfield. Advantage: Boston Red Sox.
There's a reason why the Red Sox are one of the best teams in baseball. Their bats are rightfully heralded as some of the best in baseball, but their defense is a solid compliment to a deadly offense. Aside from Brock Holt and Hanley Ramirez, there really aren't any weak points in the defense. Cleveland, on the other hand, has quite the adventure in the outfield as well as fairly weak defense at first base. The defense up the middle for both teams is incredible, and both catchers seem to throw out every base runner that tries to steal against them. If Tribe pitchers can keep the Red Sox from hitting the ball out of the infield, they should be fine.