Perhaps no position in baseball is more hit or miss than that of a relief pitcher. More than a few teams have a revolving door of relievers throughout a season, and it’s becoming more commonplace for clubs to use a closer by committee rather than an established ninth-inning arm.
At the same time, relievers are more important now than ever. With arm injuries skyrocketing, the average innings per start is on a downward swing as teams remain cautious about the usage of starting pitchers. The need for multiple stud relief pitchers to compete for a division title has been amplified in recent years.
With over 200 relievers in the league at one time, it’s hard to keep up with them. Almost 20 games into the 2025 MLB season, several under-the-radar bullpen arms are pitching at an All-Star level.
Randy Rodriguez dominating for the San Francisco Giants
The San Francisco Giants might have developed a gem in Randy Rodriguez. The Dominican-born right-hander is pitching lights out in his second MLB season and is quickly establishing himself as a go-to guy for manager Bob Melvin.
Rodriguez has yet to allow a run in nine appearances, surrendering only six hits with no walks or hit batsmen. He struck out 13 of the 32 batters he faced through April 16 for a 40.6 percent strikeout rate.
A glance at his Baseball Savant page shows plenty of red. His expected ERA, fastball velocity, chase rate, and strikeout rate are all in the 90th percentile or higher. Rodriguez uses his fastball and slider equally, but the latter is his put-away pitch. Opponents are hitting .182 off his slider, with nine of his 13 strikeouts coming from it.
Rodriguez hasn’t thrown in the eighth or ninth inning this season… yet. It’s hard to imagine the Giants keeping him cooped up in the middle innings for much longer if he keeps pitching like this.
The Chicago Cubs have found their set-up man
If you’re a diehard baseball fan, you might know the name Porter Hodge. The Chicago Cubs’ right-hander made his MLB debut last May and pitched incredibly well. Hodge finished his rookie season with a 1.88 ERA and nine saves in 39 appearances. Opponents hit a measly .132 off him.
Hodge continues to fool hitters in the early portions of 2025. Although he’s given up a pair of earned runs in nine games, opposing hitters are struggling to make good contact against the 24-year-old. Hodge’s hard-hit rate of 14.3 percent is in the 100th percentile according to Baseball Savant. The average exit velocity on batted balls against him is 85.8 mph.
Porter Hodge, Wicked Sweepers, 🤢 pic.twitter.com/2jPFkx7XNn
— Rob Friedman (@PitchingNinja) April 14, 2025
Hodge uses a two-pitch mix with a fastball and a devastating sweeper. He used his sweeper 37 percent of the time last year, generating an insane 51.8 percent whiff rate. This year, his usage rate is 48.3 percent, and although he’s not generating as many swings and misses, opponents still can’t square it up.
The Cubs have one of the league’s best late-inning duos with Hodge dominating and Ryan Pressly recently finding his form. Good luck to anyone trying to mount a comeback against Chicago.
Bryan King turning into devastating lefty option for the Astros
Having a strong southpaw in the bullpen is crucial for any team’s success. The Houston Astros seem to possess that in second-year major leaguer Bryan King. The 2019 draftee made his debut last summer and is here to stay, showcasing a brilliant start to his first full season.
King has scattered just seven baserunners through nine appearances. Only three of them came via a hit. Opponents have a .103 batting average against King with a batting average on balls in play of .188. That is the definition of unhittable.
The 28-year-old has not allowed a hit against his sweeper, which has a nearly 18-inch break. He runs it inside on right-handed hitters, making it nearly impossible to make contact. His hard-hit rate is in the 99th percentile.
King already has four holds and hasn’t allowed a run through April 16. The lefty is Houston’s best late-game option outside Josh Hader, forming a scary southpaw duo.
Reds veteran starting to find his footing
The Cincinnati Reds quietly built one of the best bullpens in baseball. A lot of that comes from the resurgence of right-hander Tony Santillan. A second-round pick by the Reds in 2015, Santillan’s professional career has been a rollercoaster. He finally seems to have established himself at the major league level.
Santillan’s numbers are impressive enough through 10 games. He has a 0.84 ERA with 10 strikeouts and three hits allowed. His efficiency is what makes him worth talking about. Santillan is averaging just under 11 pitches per inning this year. He was perfect in five of his first 10 outings.
He isn’t flashy, with only two offerings on the mound (fastball & slider). His fastball has tail on it that runs in on righties and away from lefties. Santillan has allowed just one hit and struck out eight with a fastball so far.
The 28-year-old eclipsed 100 MLB innings this season after nearly 600 in the minors. In his 10th year with the Reds organization, Santillan is making himself a mainstay in Cincinnati’s bullpen.
