Mitch Garver: The Minnesota Twins next long term catcher

The Advanced Stats

If we check out Garver’s expected stats on Baseball Savant, MLB’s Statcast-based tool, to try and see if he’s playing beyond what he should be, there’s good news there too. Savant lists Garver’s expected batting average (xBA, a measure using Statcast data such as launch angle and exit velocity to predict what a player’s batting average should be) to be a bit lower than his actual season average (.250 vs .264), but that’s not a drastic difference.

Additionally, it is worth mentioning that there’s currently no way to view expected stats over a specific time frame, so this .250 xBA does include his early season struggles, which I’m guessing helps suppress that estimate. If we turn our attention to slugging percentage and expected slugging percentage (xSLG), good news there- Savant has calculated a xSLG of .418, which is dead on with his season total.

Finally, we’ll look at weighted on base average and expected weighted on base average (xwOBA). Bear with me on this one. Per MLB, weighted on base average is a measure that takes into consideration “how a player reached base, instead of simply considering whether a player reached base”. Put more simply, it uses more information than the traditional on base percentage statistic in attempts to get a better idea of how good a batter is regardless of how an individual at bat may have turned out. Expected weighted on base average again just uses Statcast data to predict what a reasonable wOBA for a player may be.

Say, for example, Garver were to smash a line drive down the third base line with an exit velocity of over 100mph off the bat, but the third baseman were to make an incredible defensive play to turn an easy double into a lineout. xwOBA wouldn’t punish Garver as much for that result since even though it was an out, it was a great hit off the bat, whereas wOBA or OBP would simply see that Garver made an out, not caring that it really should have been an extra base hit. Anyways, what you really need to know is that Garver’s 2018 actual wOBA sits at .325 while his exOBA sits at .322, which is a negligible difference.

Apologies for the quick advanced stats tutorial, I know it can get pretty cumbersome, but there is a lot we can learn from using some of these newfangled statistics. The bottom line that we can take away from these advanced stats is they support the notion that Garver is a quality major league hitter performing at a sustainable level.

Say, hypothetically, that Garver’s actual batting average sat at .300 on the season, but his expected batting average sat at .200. This is an extreme example, but it would suggest that Garver, for whatever reason, is hitting much better than he should be, and that he’s due for significant regression in the future. That’s not the case here, these advanced metrics are very near to Garver’s actual stats for the season, which tells us that what he’s doing is sustainable and it’s not at all unreasonable to expect him to keep up what he’s been doing.