Robbie Grossman Pulls a Two-Year Deal From Detroit
Just like last offseason, the Tigers turned to a veteran free agent to aid their beleaguered offense. Yesterday, they signed Robbie Grossman to a two-year deal with a $10 million guarantee and an additional $1 million in incentives, per Cody Stavenhagen and Ken Rosenthal of The Athletic. Craig Edwards had Grossman towards the bottom of our Top 50 free agents ranking, estimating he’d get a one-year deal worth around $6 million, while the crowd had him pegged for an average of just over a year and a half and $9 million.
| Name | 2020 ISO | 2019 ISO | Diff |
|---|---|---|---|
| Wil Myers | 0.318 | 0.179 | 0.139 |
| Robbie Grossman | 0.241 | 0.107 | 0.134 |
| Luke Voit | 0.333 | 0.2 | 0.133 |
| Ronald Acuna Jr. | 0.331 | 0.238 | 0.093 |
| Jose Ramirez | 0.315 | 0.224 | 0.091 |
| AJ Pollock | 0.291 | 0.201 | 0.09 |
| Brandon Crawford | 0.209 | 0.122 | 0.087 |
| Jose Abreu | 0.3 | 0.219 | 0.081 |
| Juan Soto | 0.344 | 0.266 | 0.078 |
| Wilmer Flores | 0.247 | 0.17 | 0.077 |
Grossman’s 38 point boost to his wRC+ was the 13th biggest improvement among that same group and gives the Tigers two of top-15 offensive improvers from 2019 to 2020 — Jeimer Candelario upped his wRC+ from 72 to 137, the second biggest improvement last year.
So what was the driving force behind this power surge? Like so many other players who enjoy massive changes at the plate, a swing change unlocked this new level of performance for Grossman. After being non-tendered by the Twins in November 2018, he signed with the A’s but struggled in his first season in the Bay Area. During the offseason, he committed to making significant changes because he saw his career hanging in the balance. “I wasn’t the player I wanted to be,” he told Alex Coffey of The Athletic in an August interview. His task was made doubly hard because he had two swings to overhaul, but the results speak for themselves.
Here’s a left-handed swing from 2019, prior to his sweeping adjustments:
And here’s what that swing looked like in 2020:
The differences are subtle. The pre-swing stance is basically the same and the leg kick is a little more pronounced. But his pre-2020 swing relied heavily on his upper body to produce most of his power. To unlock his latent power, he focused on using his legs to drive the ball while keeping his head still through his swing to give him more consistency. The results were career highs in average exit velocity, hard hit rate, and barrel rate.
He only had 24 plate appearances against left-handed pitching in 2020, so it’s a little difficult to tell if those swing adjustments transferred to his right-handed swing as well. Historically he’s done very well against left-handed pitching (career .335 wOBA vs. LHP). It’s possible his swing changes weren’t nearly as refined for his right-handed swing as they were for his left-handed swing so the A’s protected him against southpaws to avoid exposing a swing that was a work-in-progress.
Hitting the ball harder should result in more positive batted ball outcomes but Grossman also started pulling the ball much more often too. He had pulled the ball around a third of the time prior to 2020 but upped that rate to 47.7% last year. That was the 20th highest pull rate among qualified batters and represented a dramatic change in approach. Driving the ball to his pull side maximized all that extra oomph he was generating with his new swing. Of those pulled batted balls, 42.4% of them were hard hits, a five point increase over his pulled hard hit rate in 2019.
With his new swing came some changes to his plate discipline as well. His swing rate jumped up five points, from 38.2% to 43.4%, and that came with a corresponding jump in his chase rate. Specifically, he started swinging at non-fastballs more often with most of his additional swings and misses coming against breaking balls. That newfound aggression led to a higher whiff rate and strikeout rate, but all his power gains offset his waning plate discipline. Honing his approach to filter out those poor swing decisions while maintaining his aggressiveness against pitches in the zone would go a long way towards making him a complete hitter who can get on base and hit for power.
The Tigers graduated (or nearly graduated) some of their top pitching prospects last year but they’re not out of their rebuilding phase yet. By signing Grossman to an affordable, short-term contract, they are building a bridge to their next contending roster. Grossman’s growth at the plate in 2020 makes him one of the better hitters on Detroit’s roster. Between honing his plate discipline and ongoing work on his swing mechanics from both sides of the plate, there’s still room to grow and continue making adjustments. He makes their offense better now while not really blocking any of their top prospects in the outfield. He likely won’t be part of the next contending Tigers roster, but he makes them a little more watchable now.
