I recently wrote a piece for RotoGraphs on Francisco Lindor, and how he appears due for a rebound in batting average, even if he maintains his 2017 gains in launch angle and flyball rate. You should check out the piece for a full explanation, but the short version is that Lindor was apparently robbed of several base hits on what xStats calls “dribble balls.” These are grounders hit with a negative launch angle.

That probably sounds counter-intuitive. How can you get robbed of hits on dribblers, some of the weakest hit balls put into play? According to the data on xStats, most hitters bat somewhere in the vicinity of .200 on dribblers. Getting a hit on a dribbler is not a high probability move, but it’s far from impossible.

As the graph below shows, a few hitters even exceeded .300 on dribblers. Delino DeShields, Kevin Kiermaier, Tim Beckham and Bryce Harper all hit at least 75 dribblers in 2017, and all crossed the .300 threshold. DeShields and Kiermaier are particularly speedy, and Harper was among the leaders in ground ball exit velocity. (Beckham’s high batting average is more of a mystery, so I may target him for further study.)

NOTE: Click on the full screen icon in the lower-right corner of the graphic for a more detailed look.

It’s also apparent (and unsurprising) that it’s much harder to get a base hit on a dribbler if you’re slow. The least speedy batters appear in red in the graph, and they are littered across the lower portions of the grid. Neither Jose Osuna nor Luis Valbuena hit above .060 on dribblers, and neither are particularly fleet of foot.

Lindor was not alone in being a relatively fast runner and having a below-average batting average on dribblers. This graph shows all hitters that hit at least 50 dribblers and had a sprint speed between 28.0 and 28.5 feet per second. Jose Ramirez, Rougned Odor, Ben Revere, Jose Peraza and Dexter Fowler all fared slightly worse than Lindor, and Eduardo Escobar batted a paltry .063 — 90 points below Lindor’s mark. While each of these hitters deserves a closer look, Escobar in particular could be a candidate for a batting average surge in 2018.

It’s not often that the least dangerous of ground balls are worthy of our attention in fantasy, but in a few cases, they can be the key to finding players due for a surge or decline in batting average. Lindor is one of the most interesting of these cases, but I’ll be looking at several other of these 2017 outliers in the coming weeks.