It's hard to look at Gavin Lux's start to 2024 and get too excited. Finally healthy and with an extended run at a permanent position, he's hit his way to a slash that includes a .204 average & .259 on-base percentage. His wRC+ is at just 58, while a .075 ISO indicates virtually no power to speak of.
Lux is, notably, working through some swing mechanics & experiencing some timing issues as a result. He really isn't considered a full-time starter, as he's already sat quite a bit against lefties. FanGraphs also projects him for roughly 60 percent of the playing time at second base moving forward. There are questions about his longer-term role, to be sure.
At the same time, it's at least worth discussing the one aspect of his game that has been positive: the defense.
We're starting to reach a point where defensive metrics are gaining enough of a sample to be considered useful. And there are a few at which we can point to show Lux's value in that respect.
First is Statcast's Fielding Run Value (FRV). A fairly new metric, this is meant to be a comprehensive look at a player's defensive value, above or below an average threshold of '0'. Lux is at a FRV of 1, indicating that he's an above average defender (even if only slightly so).
From there, we also have the more familiar Outs Above Average (OAA) & Defensive Runs Saved (DRS). These are somewhat preference-based, as the onus is on the reader to determine if they like their defender to record outs or prevent runs. Because those are not the same thing (a deeper discussion for another time).
Nonetheless, Lux comes out looking good in each. He's at 1 OAA for the season, but he's at a DRS of 5. The latter figure trails only elite defender Marcus Semien & much-improved defender Ketel Marte. So while the Statcast metrics don't love him as much as they love some of his keystone counterparts, the ol' reliable DRS certainly does.
One of the more impressive elements of Lux's glove lies in his success rate. Baseball Savant has him at an estimated success rate of 83 percent on defensive plays. Lux is at exactly an 83 percent success rate, overall. He's been perfect on plays straight up & slightly ahead of his estimated success rate in either direction. In short, he's been very good with the glove.
Given the availability of other options (Miguel Rojas, Miguel Vargas, etc.), we don't know how long Lux's defensive competence will allow him to maintain a grip on second base. It is a position where the offensive profile isn't outlandish, with the exception of the very best bats (for added context, less than half of second basemen with at least 120 plate appearances are above average by wRC+).
So it's possible that he gets a little more runway, especially if the rest of the lineup continues to pick up the pace offensively as they did in Queens this week. Defense will only allow you to maintain a grip on a starting role so far, though. While Gavin Lux's has been very good, it's difficult to know if it'll have a positive bearing on his future in the way that the bat has potentially had a negative one.