Analysis: Why Mariners’ Julio Rodriguez could be ‘close’ to rediscovering home run swing

SEATTLE – Before the start of the MLB Home Run Derby at T-Mobile Park last summer, Ken Griffey Jr. and Julio Rodriguez sat together for a few minutes in front of the home dugout.

The Mariners’ hall of fame center fielder had one suggestion before the Mariners’ young center fielder stepped to the plate in front of an adoring home crowd.

Hit the ball out front, Griffey told him.

Rodriguez did plenty of that, launching 41 home runs in the first round in a power display never seen before in the Home Run Derby.

No one who was there will soon forget the electric atmosphere, and the memory of that night only serves to heighten one lingering question surrounding the Mariners star now:

What happened to Julio Rodriguez’s power stroke?

Rodriguez has hit only one home run through the first 38 games of the season after hitting 60 over his first two big-league seasons.

And while his batting average (.262) isn’t far off his career average (.279), his slugging percentage of .315 is considerably below his career mark of .495 coming into this season.

Conclusion: He’s lost his launch.

Rodriguez has a launch angle of 8.8 degrees this season, ranking well below the MLB average (12.9) and marking a drop-off from his 10.1-degree average angle during his rookie season.

In short: He’s not hitting the ball in the air enough.

An ideal launch angle for a home run – that is, the angle at which the ball leaves the bat – is in the range of 25 to 30 degrees. Anything under 10 degrees turns into a ground ball. Anything over 50 degrees turns into a popup.

So how does a hitter improve his launch angle? And how important is it to hitting home runs?

“Your swing path plays a big role,” Mariners hitting coach Jarret DeHart said. “And Julio generally has a relatively steep swing path compared to most people. He’s steep getting into the (hitting) zone, and then he stays in the zone for a long time once he’s there.”

That last point is important with Rodriguez because that’s part of what has made him an elite hitter – his ability to get the barrel in the zone and keep it in there through his swing longer than the typical hitter.

To hit a home run, though, Rodriguez generally has to make contact with the ball out in front of the plate, as Griffey suggested before the Derby.

That’s true of most hitters – get to the ball in front of the plate to launch it – but it’s even more pronounced for Rodriguez because of his bat path.

“You think about the arc (of a swing) – it’s going to start on a downswing, and then eventually it’s going to turn up,” DeHart said. “No matter how your swing works, there’s always a downswing and then an upswing. For him, his upswing happens farther out front than most people because it’s a relatively steep path.

“So for him to hit the ball in the air consistently, it has to be out front. That’s where timing and intent all that stuff come into play, because if he’s catching it too deep in the zone it’s basically going to be impossible for him to get it in the air.”

There are encouraging indicators for Rodriguez. Here are a few, from MLB Statcast metrics:

• He is still hitting the ball about as hard; his 92.4 mph average exit velocity is nearly the same as it was last year (92.7). And his hard-hit rate of 49.5% still ranks in the 88th percentile among MLB hitters. The best way to hit a home run … is to hit the ball hard.

• His launch angle is starting to creep up. His average stood at 7.5 degrees on May 2, and it climbed to 8.8 degrees over the past week.

• His ground ball rate has dipped a bit from last year (to 44.1% from 47.6% in 2023). His line-drive rate, however, has increased significantly (up to 27.5% from 18.5% in ’23). No hitting coach is going to turn down a hard-hit line drive, but to hit home runs you (almost always) have to elevate the ball.

• During his scorching streak last August – in which he hit .429 with seven homers, 10 doubles and a 1.197 OPS – he had an average launch angle of 9.8 degrees across 105 at-bats. That suggests Rodriguez doesn’t need as much launch as a typical hitter to do damage – serious damage.

One other statistical difference that stands out in Rodriguez’s profile: He’s not pulling the ball nearly as often as he did the past two seasons, down to 31.4% from 42% last year.

His hits to the opposite field, meanwhile, have increased a bit (to 28.4% from 23.7% last year).

“The fact that you’re able to take an inside pitch and hit it the other way with authority says a lot of good things about your path,” DeHart said. “We just need to extend that same path and catch it a tick more (out front) – I mean, we’re talking just a couple inches. And he’s getting close.”

Many things have to go right for a hitter to hit a homer, and the launch angle is only one factor. One consistent factor, as manager Scott Servais references often, is for a hitter to get into a good count.

“You have to earn your pitches to hit by laying off the bad ones,” Servais said recently.

Rodriguez’s one home run this season came on a 1-0 count.

In his 161 plate appearances, Rodriguez has been in a 2-0 count 15 times, with six walks and two hits in those situations.

He’s been a 3-1 count nine time, with seven walks and one hit on two balls in play.

Pitchers are aggressively pitching Rodriguez with fastballs inside early in the count – often off the plate inside – and then with sharp sliders away late in counts.

“With Julio, it’s about staying aggressive, swinging at the right pitches and understanding how teams are going to pitch to him,” Servais said. ” … For me, it’s about making sure – what pitches are you looking for? And when you get a pitch in that zone, then just be Julio – be aggressive and take a whack at it.

“When he stays behind the ball, the ball goes in the air – and it’s electric.”