When splitting up the performance for Oakland Athletics third baseman Matt Chapman between the first and second half, we have a bit of a sample size problem. That doesn't mean he still didn't recover from a slow start and end his rookie campaign on a high note, though.
In his 42 plate appearances prior to the All-Star break, the third baseman posted a 9 wRC+ and a .187 wOBA. His strikeout rate was 47.6%, and for a guy that posted a .331 ISO in 204 Triple-A plate appearances prior to his promotion, his power was non-existent (.053 ISO) in the big leagues. But after having a tremendous start to his second half, he continued that above-average production all the way to the end.
Through his final 284 plate appearances, Chapman posted a 123 wRC+ and .353 wOBA while watching his strikeout rate dip all the way down to a much more manageable 25.4%. His power also returned -- his 14 home runs in 2017 all came after the midsummer classic, with his .266 ISO during this time more closely resembling what he accomplished in the minor leagues.
It's hard to draw firm conclusions between these two periods of time because the sample sizes are so different, but Chapman settled in and started producing by dropping his chase rate just over 10 percentage points while his overall contact percentage improved almost 15 percentage points.
One thing that didn't change much was his fly-ball rate, which was at least 50.0% during each time period (55.6% in the first half, 50.0% in the second half). That gives him some intriguing upside heading into 2018, especially when that rate accompanied with a season-long hard-hit rate of 36.0%.