clock menu more-arrow no yes mobile

Filed under:

New Tigers outfielder Robbie Grossman showed signs of a breakout in 2020

Underlying metrics suggest he can keep it going in Detroit.

American League Wild Card Game 3: Chicago White Sox v. Oakland Athletics Photo by Daniel Shirey/MLB Photos via Getty Images

The response to the Detroit Tigers signing of veteran outfielder Robbie Grossman has been quietly positive, and with good reason. Yes, the 31-year-old switch hitter has spent his career as a decent strong side platoon player. He’s not going carry an offense, and until 2020 had never posted the type of power marks to carry him to another level. We were certainly hoping for more of a proven power threat. However, Grossman is a professional hitter who consistently does two things quite well. He gets on base, and he doesn’t strike out much.

On the surface, this isn’t terribly exciting, though it is a change of pace for a Tigers offense regularly plagued by free swingers. Grossman’s patience at the plate and ability to battle through tough at-bats to put the ball in play should be good examples for younger hitters on the club to emulate. Against righthanded pitching he’s going to produce above average offense to some degree, steal a few bags, and play at least average left field. More intriguing, are the changes Grossman made in his game over the past year that say he may well outperform those expectations in 2021.


The two factors that have kept Grossman from developing into a good everyday player prior to 2020, at least via the various WAR calculations, are his defensive skills, and his lack of power at the plate. Those issues, and the fact that he’s a strong-side platoon hitter, held him back throughout his twenties. There have been any number of articles written over the years speculating as to what Grossman could become if he unlocked more from those skillsets. In 2020, he finally appeared to make that leap in both regards.

After three years with the Houston Astros, and three with the Minnesota Twins, Grossman reached free agency after the 2018 season. He found there wasn’t much call for his services. The Twins made no push to bring him back, and he ultimately settled for a one-year deal worth $2 million with the Oakland Athletics. Since that point, his defense has begun to improve substantially. He’s still a left fielder, and the positional adjustment makes it tough to be very valuable unless you’re playing a really left field, but his numbers have consistently improved, and took a real leap in 2020.

Here are Grossman’s Outs Above Average marks (OAA), accumulated mostly in left field, over the past four seasons.

2017: 0 outs above average

2018: -1 outs above average

2019: +2 outs above average

2020: +4 out above average

Grossman’s defensive ability has never been a function of a lack of speed. He’s not a burner by any means, but his sprint speed of 27.5 ft/sec in 2020 ranks him 150th in the league out of 454 players with a measurement on Statcast, and in the company of players like Kris Bryant and Francisco Lindor. Not exactly fast, but a little better than average and capable of stealing some bags. In any event, Grossman’s speed marks have been very consistent the past few years. He doesn’t appear to have improved in that regard. The explanation for his defensive improvements lie elsewhere.

Whether a matter of health or experience, better technique, more emphasis on his defensive work, or simply a lack of Midwestern weather, Grossman has sustained improvement year after year. But his marks in 2020 are on a whole new level. We’ll happily take anything average or better with JaCoby Jones and Victor Reyes providing good coverage alongside him.


Better defense is nice, but this is the real crux of the biscuit. While on-base percentage is hugely important, and long ago supplanted batting average as the key indicator of a hitter’s skill level, it’s not enough on its own. Grossman has a career OBP of .350, which is excellent. League average in 2020 was just .322. That on-base ability is backed by a walk rate of 13 percent and a strikeout rate of just 17.9 percent over the last four seasons. What he’s lacked is power, and more than anything else, his meager home run totals have held him back from receiving serious interest in free agency.

Major gains in that regard in 2020, backed by several key indicators, hint that he may have finally unlocked more of his raw power at the plate. It’s worth noting again, that he only had 24 plate appearances as a right-handed hitter in 2020, so this damage is basically all as a left-handed hitter.

Robbie Grossman 2017-2020

Season PA wRC+ ISO Avg EV Barrels Hard Hit % Avg Launch Angle LD% GB% FB% IFFB%
Season PA wRC+ ISO Avg EV Barrels Hard Hit % Avg Launch Angle LD% GB% FB% IFFB%
2017 456 103 0.134 86.4 9 26.7 12.2 24.8 40.7 34.4 8.7
2018 465 109 0.111 87.1 6 27.8 15.1 24.2 38.7 37.1 10.2
2019 182 88 0.107 87.7 7 30.7 12.1 25.1 40.6 34.3 5.2
2020 192 126 0.241 89.0 7 37.5 15.2 22.7 39.1 38.3 6.1

There’s an awful lot to like in those 2020 numbers. Grossman was on pace for a 20 HR/20 SB season for the A’s. The shortened season naturally creates skepticism that he can sustain this level of damage. However, look at some of the key indicators like average exit velocity, hard hit rate, and barrels. He didn’t just happen to flip a few more balls out of the park. Instead, he was consistently driving the ball with authority like never before.

Grossman posted the highest average exit velocity and hard hit percentages of his career. He also sustained a launch angle over 15 percent. When you do that while hitting the ball harder, still hitting plenty of line drives and rarely popping the ball up, you aren’t just on a tear and getting lucky. Success like Grossman’s has the scent of sustainability to it and he no doubt had a few teams’ attention this offseason.

There are some notes that signal a change in Grossman’s approach, in that his overall swing percentage went from a career mark of 38.7 percent to an all-time high of 43.3 percent, indicating that he was more aggressive. In the process, he did swing at more balls out of the zone, and his swinging strike rate was the highest its been since 2016. In Grossman’s case, none of that is a concern, as his consistent discipline left him plenty of room to swing more freely while handily putting up better than average marks in both O-swing percentage and swinging strike percentage. The improvement in his power marks was decisively worth those modest tradeoffs.

The final key is that Grossman managed to do all these things while boosting his pull percentage to 47.7 percent of balls in play, over 10 percent more balls to the pull field than his career averages. He’s always been an all fields hitter, but in 2020 he managed to turn on more balls, while at the same time making gains in his contact quality. That’s a good recipe for power if he and new Tigers’ hitting coach, Scott Coolbaugh, can keep it going in Detroit.

For his part, Grossman attributes his excellent 2020 campaign to some offseason work with A’s hitting coach Darren Bush. In a piece by Matt Kawahara for the San Francisco Chronicle back in August, he described the adjustments, albeit rather vaguely.

Grossman said he began working last offseason with guidance from A’s hitting coach Darren Bush to shift his body position in order “to use my legs and use the ground as force” and that the change is “helping me to consistently square up the ball.”

In the same piece, manager Bob Melvin describes his work a little more clearly as an attempt to to stay back and balanced rather than allowing himself to drift toward the mound. This isn’t particularly revelatory advice, of course. Most hitters are trying to do that more effectively. The difficulty is in trusting that adjustment and sticking with it during games.

In 2020, Grossman was able to do so on a pretty impressive scale. Hopefully he can carry that feeling into Comerica Park and provide the Tigers’ offense with a real spark in 2021.

The Tigers did well here

Since the 2017 teardown began, the Detroit Tigers haven’t signed a single player to a multi-year deal. It may come as a surprise that Robbie Grossman was the first to receive that vote of confidence from general manager Al Avila. But there appear to be quite good reasons for it. We’ll have to see if he can sustain his 2020 gains, but either way he certainly appears to be an improved player from his time with the Minnesota Twins.

For just $5 million per year plus some incentives, this appears to be more the type of bargain fans should be hoping for. While we’d prefer to see them open the pursestrings and pursue bigger game as the offseason plays out, Robbie Grossman is the right kind of inexpensive player to acquire. Rather than just signing a mediocre player without upside on the cheap, they’ve found themselves an outfielder with a strong floor as a solid veteran player, and some promise of above average production in a Tigers uniform. Find a few more players like that, and with a little help from their farm system the Tigers could be surprisingly fun in 2021.