And they miss the obvious reason.
Xander might be ninth not because of what he does. But because 8 other shortstops do it better...
I admit, I have watch almost no MLB games not involving the Sox over the 50 years I've followed baseball. I have watched some Astros games recently, but no where near the amount of Sox games.
That being said, I know I have seen plays made by visiting SSs that I've never seen Bogey make. It's not just one here or there either. It's enough for me to know Bogey is not even close to being the best defensive SS in MLB.
I like UZR/150, and I think it is much more accurate than me or any other fan watching mostly just Sox games and looking at Flg% and RF/9 like the old days to try and determine what ranking our defenders should have in the pecking order.
Most posters know I was a big Iggy fan and have always highly valued, perhaps too much, SS defense. I was one of those posters suggesting we move and keep Bogey at 3B. Maybe I'm still biased against his defense, but I did admit he progressed more than I thought he would a couple of years ago aafter his decent 2015 defensive season. Now, I'm not so sure about his "progression". I felt he took a slight step backwards last year, on defense, and he hasn't shown any growth this year. The UZR/150 supports my opinion, but we no longer have an Iggy in our system, so I see no reason to move him off SS for the foreseeable future.
Right now, Bogey ranks 18th out of 29 in UZR and 15th out of 29 in UZR/150 at barley a plus (+0.7). Look, I'm thrilled to have an average fielding SS who is hitting over .330, but that doesn't mean I'm not disappointed that his defense seemed to stop improving after 2015.
Bogey's UZR and UZR/150 at SS since 2014:
Year UZR UZR/150
2014 -2.7 -3.7
2015 +1.0 +0.9
2016 -2.9 -2.8
2017 -0.1 +0.7
What gets me most is his range numbers, although they look better this year than past years:
2014: -2.3
2015: -4.6
2016: -3.5
2017: -0.8