Numbers support Twins decision on Byron Buxton's non call-up

The big story of the unofficial last weekend of the summer was the Twins' decision not to bring Byron Buxton to the majors as a September call-up.

There are all sorts of well-reasoned takes on the issue, including the notion that Derek Falvey and Thad Levine come off looking bad because the decision appears motivated by keeping Buxton from gaining the service time needed to be a free agent a year sooner. Maybe that's the way the game is played, but the optics are bad.

From a purely baseball standpoint, though, there is evidence that Buxton has not earned a promotion — nor would him coming up and succeeding for a few weeks prove anything about his readiness for 2019.

Let's take a closer look at a few notable statistics from Buxton's career:

• On the subject of September proving nothing, there's this: Buxton has feasted in the majors as pitching has thinned out in the later months of seasons throughout his career.

His career OPS (on-base plus slugging percentage) in the majors by month: April, .464; May, .548; June, .546 — all awful. That includes a rough start this season (.195 average with the Twins) before health problems became apparent.

Then he starts to pick things up in July (.739) before hitting a stride in August (.818) and September (.853).

• There were genuine reasons to be excited about Buxton coming into 2018 based on his second half in 2017 and a magic number he was quickly approaching.

Buxton entered 2018 with 980 career major league plate appearances, and there are some who believe 1,000 plate appearances is a key marker in a hitter's development. But if the thought was that Buxton had turned a corner last year as he approached that milestone, this year brought a regression in all areas.

The most telling advanced stat, per Baseball Info Solutions: Buxton in his 94 plate appearances with the Twins this season swung at 39.4 percent of pitches outside the strike zone. In his career entering the season, he was a little above 30 percent.

Maybe playing through an injury this season messed up his swing, leading to that uptick. But it's still concerning that his command of the strike zone as a hitter seemingly got worse.

• Buxton supporters point to his .365 average during a recent stretch in Rochester as justification for a September recall, but let's not confuse a 12-game hot streak at Class AAA in the second half of August for a meaningful turnaround with Buxton. In 23 other Rochester games this season, Buxton hit just .217.

What Buxton needs to show in 2019 is that he can hit and stay healthy consistently for the duration of a major league season, including the beginning when all 30 teams are fully engaged.