Why Nationals relievers have tested out new pitches

Thompson, though, believes tinkering with potential pitches has aided the ones he is more likely to throw. Sean Doolittle, another Nationals reliever, agrees. With only so many pitches in their offseason tank, relievers need to carefully divvy their reps between practical and experimental. Yet in trying to expand their arsenals in recent years, both Thompson and Doolittle learned a bit about themselves.

“You have to know who you are. You have to take care of what you’re good at first,” said Doolittle, who’s 36 and could start the season late after undergoing elbow surgery last summer. “But after that, I feel like there’s a lot to gain from trying to throw something you’re maybe not too familiar with. Because even if you don’t get to what you were initially going for, you might look at the TrackMan [data] and say, ‘Oh this shape actually doesn’t pair too well with my main pitches, I need something with more depth.’ Or you look at the Edgertronic [camera] and notice something about your grip. There’s a lot to glean.”

“I mean starters get to have all the fun, right?” Thompson said with a laugh. “Every one of them seems to come in here saying they’re going to throw this or that. Us relievers want to get involved, even if we don’t always take it into games.”

In 2022, Thompson threw 268 sinkers, 88 sliders, seven four-seamers and five change-ups, according to Statcast. Sinkers accounted for about 75 percent of his total pitches. Then this past winter, he filled his bullpens with sinkers, sliders, four-seamers, change-ups and curves, surprising hitters in live batting practice and refining his slider along the way.

Maybe the 25-year-old sneaks a curve or two into an appearance soon, either in spring training or at the start of April. At times over the offseason, he felt it was his better breaking pitch. He also figures it can’t hurt to put something else on scouting reports, stashing another possibility in the back of hitters’ heads. But more than anything, throwing the curve taught him to get more “out in front” with his slider, waiting to manipulate his fingers and wrist until right before he releases the pitch. He called that a “critical realization.”

Whether he can keep tinkering in spring training games is a different story. Thompson, who joined the Nationals at the 2021 trade deadline, is still fighting for a stable roster spot. He has one minor league option year remaining, meaning he could swing between the majors and minors this season without going on waivers. Against the Miami Marlins on Thursday, he pounded sliders in a rough outing to test pitch. Manager Dave Martinez wanted to instead see more high-90s sinkers, the pitch the staff believes in most.

“I keep telling these guys: When you work on stuff, it’s got to be on the backfields,” Martinez said after the 5-5 tie in West Palm Beach. “When you come into games, we’re competing. I mean we’re out there trying to win the ballgame. It’s early and they want to tinker with different things … I know they want to see how it works in games. But we got room for that. If they want to do that, we can set something up for them.”

In Doolittle’s 11-year career, he’s thrown a four-seam fastball 87 percent of time, lighting mixing in a breaking ball and change-up. Then two offseasons ago, the lefty tried learning a sweeper slider — a pitch with much more side-to-side movement than his usual breaking ball — and got a lot out of the experiment, which failed in that he never threw a sweeper in a game, but succeeded in that it helped shape the off-speed pitch he leaned on before injuring his elbow last April.

The sweeper itself had pros (about 20 inches of horizontal movement) and cons (Doolittle couldn’t throw it harder than 70 mph). But throwing it led to better feel and hand action for the breaking ball he debuted before his injury last spring. In the tiny sample of 55 pitches, Doolittle’s fastball rate dropped to 74.5 percent, a career low, while his breaking ball jumped to more than 20. And in another tiny sample, Doolittle retired 16 of the 17 batters he faced.

“The key, if you’re working on something new, is to deliberately mix in your trusted pitches,” Doolittle said. “Like if you want to learn a cutter but throw a great four-seam fastball, go cutter, four-seam, cutter, four-seam in your pens. The worst thing that can happen is you lose your four-seamer. The best thing is you now have an electric cutter.

“The upside, somewhere in between I guess, is improving something else.”