Mike Moustakas is a good player.
Not a great one, mind you, but he’s been a solidly above-average regular since breaking out with the bat back in 2015. He’s hit .267/.324/.484 for an OPS+ of 115 since over the past four seasons, averaging 33 home runs and 3.2 bWAR per 162 games played. ZiPS projects a .267/.324/.506 slash from Moose in 2019, and PECOTA forecasts a .273/.336/.495 batting output. Very useful production.
Mike Moustakas is not a second baseman, though. Or, at least not yet.
The Milwaukee Brewers entered this winter with what appeared to be an acute need to upgrade their lineup at second base.