MLB trends: Adley Rutschman’s new game, Hunter Brown’s miracle sinker and the Giants bullpen’s weird look

It feels like Opening Day was last week, but the All-Star break is less than a month away and the trade deadline isn’t far behind that. The samples are no longer so small and competitors are starting to separate themselves from the suitors. Well, like that. There are still many teams in the soft middle as July approaches. Here are three MLB trends worth knowing about.

Adley’s aggressiveness

Entering Tuesday’s important series opener with the Yankees, Orioles catcher Adley Rutschman owned a career-best 133 OPS+, but nothing completely out of line with his 2022-23 129 OPS+. Global production is approximately the same, but the form of that production is not. After being a great hitter at the plate in 2022-23, Rutschman is trading some selectivity for power in 2024.

To be clear, Rutschman’s strikeout and swinging rates are still better than MLB averages (22.2% and 10.9%, respectively). He is attacking and sniffing more, but not excessively. He’s still making a lot of contact. He’s just doing a little less, and in return, he’s hitting the ball harder and in the air more often. As a result, Rutschman’s energy output increased.

It doesn’t take long for the word to spread in this league and opponents are already combating Rutschman’s new aggressiveness by throwing him fewer fastballs and fewer strikes. Thirty-five games into the season, Rutschman was seeing about 42% four-seam fastballs and 55% zone pitches. These numbers have since been reduced to 33% and 50%, respectively.

Rutschman responded by returning to his patient self. His chase rate increased by about 40% in the first 35 games. It’s now down to 33.4%, which is still high compared to 2022-23, but not much above the league average of 28.2%. Rutschman has found his level. He was ultra-aggressive in early 2024. Now he has reigned in a bit and appears to have found a happy medium.

The next step is to find a way to pair the plate discipline of 2022-23, when Rutschman was one of the most selective hitters in the game, with his 2024 swing. Maybe not possible! Typically you have to trade off a bit of selectivity to maximize damage. Given Rutschman’s talent and vision, I bet there’s still another level here, and he can regain more discipline without sacrificing power.

Brown’s new sinker

It’s mid-June and the Astros are still several games under .500, mainly because their rotation has been one of the worst in the sport. Astros starters had a 4.55 ERA (24th in MLB) and a 2.9 WAR (26th in MLB) heading into Tuesday’s action, and recently lost Cristian Javier and José Urquidy to season-ending elbow surgery. A starter is required by the deadline to return to the race.

Right-hander Hunter Brown, Houston’s best pitcher two years ago, has been the club’s biggest rotation liability this year. He has a 5.00 ERA in 13 starts (and one relief appearance), and that’s coming off a 2023 in which he had a 4.12 ERA in the first half and a 6.57 ERA in the second half. That’s almost a full calendar year of replacement-level production.

The arrow is starting to point up. Brown’s last eight games have been much, much better than his first six:

A tale of two pitchers, of course. So what has changed? Brown added a sinker on May 5. It was a pitch he had never thrown before in the big leagues, but he suddenly used it 11% of the time on May 5. That usage gradually increased and last time out Brown threw 25% sinkers against the Tigers. He struck out nine and held Detroit to five singles and zero walks in seven shutout innings.

Brown has shortened his fastball and four-seam cutter to make room for the sinker, which he throws almost exclusively to the arm side (in right, away from lefties). It was part of the strike zone that he hadn’t used much previously, at least not with speed. He would bury the changeups on that side of the plate and that would be it. The sinker forces hitters to respect that side of the plate now.

“It just allows him to use his other weapons,” Astros manager Joe Espada told MLB.com recently. “When you have that sinker at 95, 97 running to your hands, now you have the four seams in the zone, the breaking ball and the cutter. Now you have to protect the entire board, and it is a very challenging game in itself. When you have to cover so much of the plate, it’s almost impossible to get it right.”

Brown, a consensus top-50 prospect two years ago, showed such promise in late 2022 and early 2023 before hitters told him it was time to adjust. What he was doing wasn’t working. So Brown and the Astros went to school and developed this new sinker. It made a big difference for him and credit to Brown for making it work. Choosing a new field during the season is not easy.

Funky SF bullpen

With a 4.32 ERA (21st in MLB) and 0.8 WAR (21st in MLB) coming into play on Tuesday, the Giants’ bullpen has been nothing special this season. The unit ranks middle of the pack in terms of added win probability. It also ranks fifth in Stuff+, a metric that evaluates the tone’s physical characteristics (speed, movement, etc.). The results weren’t great, but the models love the shapes of the field.

One thing the Giants have in their bullpen is diversity. They attack you with relievers that have so many different looks and release points. Here are the pitching spots of San Francisco’s top eight relievers in batters faced (catcher’s view):

Camilo Doval and Randy Rodríguez’s release points overlap, otherwise San Francisco’s bullpen is all over the place. 6-foot-1 Sean Hjelle and 6-foot-1 Luke Jackson have similar launch heights, but they get there with very different arm slots. The two lefties (Erik Miller and Taylor Rogers) have different throws. Tyler Rogers is on his little island down there as a submariner.

Arm angle and release spot diversity became a major topic of discussion during the 2020 postseason when the Rays used a wide variety of relievers to win the AL pennant. The logic is simple: Show hitters different looks and don’t let them get comfortable blocking a similar pitching “window.” Much of the pitch is different and strange. San Francisco’s bullpen embodies this.

Of course, the Giants haven’t gotten great results from their bullpen, so maybe all those pitching spots aren’t having the desired effect. This is more of a recognition of the diversity the Giants have in their relief corps than a compliment to their success. Funky bullpens are fun and different, and no team shows hitters more unique pitches and arm angles than the Giants.