Mark Trumbo’s power output is here to stay

Mark Trumbo arrived on the Orioles with little fanfare. He’d hit a good-but-not-great .262/.310/.449 in 2015, good for an above-average but not eye-popping 108 wRC+. Most fans viewed him as a bargaining chip for the Orioles to gain leverage on the then-unsigned Chris Davis. He’d just come from his third team, and great (or even good) players generally don’t get passed around.

But his last stop, in Seattle, changed him. There Trumbo worked with hitting legend (and should-be Hall of Famer) Edgar Martinez. Said Edgar, as relayed by the Seattle Times’ Ryan Divish:

[Trumbo] was hitting more off the back leg so we worked on hitting against the front leg and releasing the back leg a little bit and keeping his bat longer in the zone.

Divish writes that Edgar also noticed Trumbo doing a “bat wrap”, which I learned is when:

The head and barrel of Trumbo’s bat [tilted] forward as he initiated the swing, almost as a trigger to action. To Martinez, that was unnecessary movement that messed with timing of the swing while adding length to it.

Thank you, Edgar! I’ve arranged for Peter Angelos to send you a portion of Scott Coolbaugh’s paycheck.

Through Saturday’s game Trumbo leads the major leagues in home runs with 28. He’s hitting .290/.342/.577 and looking for all the world like 2014 Nelson Cruz reincarnated — except better, as Cruz hit .273/.333/.525 in his Baltimore sojourn.

The great news for Orioles fans is that Trumbo’s hitting bonanza appears to be more skill-based than luck-based. Sure, he’s running the highest HR/FB rate of his career by over four percentage points. But the details show he’s not just getting lucky.

Trumbo’s changed two facets of his game: launch angle and spray angle. He’s hitting the ball in the air far more often, he’s pulling the ball more often, and he’s hitting it harder as well. This approach doesn’t work with everyone. If Joey Rickard tried it, he’d be benched. But except for 2014, Trumbo’s hit at least 22 HR each year since 2011. He has the kind of power to make this swing work.

His flyball tendencies show up in a few places, such as his ratio of ground balls to fly balls:

Confirming the FanGraphs data, his average launch angle rose from 12.5 degrees to 17.4 degrees. The sweet spot for home runs is in the 22-27 degree range. The more often you hit balls there, the better you’ll be.

Trumbo’s not only getting under the ball more, he’s pulling it as well. He’s barely hit any opposite-field home runs:

His spray angle chart shows the same strong pull to left field:

The idea behind pulling the ball is to hit it harder. Trumbo’s exit velocity increase demonstrates he’s been successful:

Woe betide any pitcher who tries to sneak a fastball by Trumbo on the inner half of the plate. As you might expect he’s hammered inside pitches all year:

Impressively, Trumbo’s adjusted his approach without sacrificing any plate discipline. His ratio of walks to strikeouts is down only a tiny fraction. He’s can somehow bludgeon inside fastballs while laying off pitches out of the zone at around the same rate he always has.

Regression to the mean may yet bite Trumbo. He is running career highs in both HF/RB rate and BABIP. But the increased launch angle, spray angle, and exit velocity show he’s not just getting lucky. He’s changed his skillset, at least for this year.

Many fans dismiss sabermetrics because it categorizes a lot of improvement as pure luck that’s due to regress to the mean. Saying a star pitcher or hitter is “just getting lucky” may be true but it leaves a bad taste in the mouth and sometimes smacks of arrogance. I get that.

But the benefit of recognizing luck is that sabermetrics also highlights true skill changes, such as the one Trumbo made with the help of his former hitting coach. Now, fans can feel better about Trumbo’s second half because he’s truly a different hitter. He’s not just relying on bad defenders or windy days at the ballpark.

So get ready, Orioles fans. Trumbo’s under threat from pitchers across the league. They’re already teasing him more with offspeed and breaking stuff, hoping he’ll bite.

But even the best pitchers miss inside with fastballs. And when they do, Trumbo’s shown he can give the Orioles the major-league home run leader for the fourth year in a row.