Top 10 Under-the-Radar Relievers Left in Free Agency

As this offseason has progressed, teams have been steadily upgrading their rosters every single day. Through all of these moves, the goal has been to refine the on-field product, slowly building towards competing in the near future.

We’re nearly halfway through the offseason, and one of the hottest commodities on the free agent market has been relief pitchers, as teams have been eager to bolster their bullpens.

Despite most of the league’s top bullpen arms by fWAR already being scooped up, there are still plenty of opportunities for teams to improve their bullpens. There’s a lot of value in some of the most under-the-radar names on the market, and the price tag shouldn’t be particularly high on most of these arms, either.

Let’s take a closer look at the top 10 under-the-radar free relievers left on the free agent market, and examine why they’re such valuable assets heading into 2026.

Michael Kopech

When it came to the 2025 season, the Dodgers had high expectations surrounding flamethrower Michael Kopech. However, a slew of injuries limited him to just 11 innings, a disappointing outcome for the former top prospect.

In those 11 innings, Kopech showed flashes of being a very solid reliever. He racked up 12 strikeouts during this span, all while pitching to an ERA of 2.45. For Kopech, the biggest concern was his control, which spiraled out of control during this span. His walk rate spiked over 24%, an incredibly concerning mark.

Although there isn’t a ton of data to examine from his performance this season, Kopech kept hard contact to a minimum. He allowed zero barrels and kept his hard-hit rate under 40%. If this continues over a full campaign, he could be one of the better relievers in the sport with a few tweaks.

For a team looking for a potential high-leverage reliever, Kopech is definitely worth the risk. If he can keep walks to a minimum and stay on the field, he has a chance to be a tremendous value-play for the team that eventually signs him.

Pierce Johnson

One of the most valuable tools a reliever can have is the ability to be available whenever the bullpen phone rings. Only 43 right-handers appeared in 65 or more games during the 2025 season, and among those players was eight-year veteran Pierce Johnson.

Aside from being one of the three most regularly used members of the Atlanta Braves’ bullpen, Johnson regularly put together quality innings. He racked up 59 strikeouts in 59 innings pitched, all while also posting an ERA slightly over 3.00 and a WHIP of 1.20.

His success is largely due to his curveball, which generated an xwOBA of .292 this year. Considering he throws it over 72% of the time, this offering has been very valuable to his game.

Johnson has steadily become a very solid option in the Braves’ bullpen during the last two seasons. In fact, this is the second straight year where he’s recorded an ERA in the threes while pitching more than 55 innings in relief.

If he can repeat this, he’ll be a quality arm that most teams could benefit from adding.

Danny Coulombe

Although there were numerous quality relievers on the free agent market this offseason, there weren’t many solid left-handers available. After a stellar showing between the Twins and Rangers this season, one of the top left-handers available, Danny Coulombe, remains on the market.

Dating back to 2021, it’s tough to find many better left-handed relievers than Coulombe. During this span, he’s pitched to a 2.64 ERA across nearly 190 appearances while also striking out 175 batters. He’s also kept long balls to a minimum, allowing just 15 in this span.

In 2025, Coulombe was elite at limiting barrels. He only allowed six all season long, a number that was good enough to keep his barrel rate just over 5%. Not only this, but opponents rarely hit the ball hard against him in general, as his opponents had an average exit velocity of 87.5 MPH against him.

For any team searching for a reliable left-handed relief option, Danny Coulombe is arguably the best arm on the board. He shouldn’t cost a ton of money, either, which makes him an even more attractive free agent.

Hunter Harvey

Over the last few years, Hunter Harvey has seen the peaks and valleys of being an MLB pitcher. He was one of the league’s top relievers in 2023, struggled in 2024, and spent the majority of 2025 on the injured list. Due to this, he has a chance to be a cheap and valuable pickup this offseason.

Although it wasn’t much, Harvey looked lights out when he was on the field this year with the Royals. He didn’t allow a single run in the 10.2 innings he pitched, striking out 11 batters along the way. He also kept walks to a minimum, only surrendering one free pass.

Whichever team signs him this offseason will be hoping to get a healthy 2026 out of the 31-year-old. If they do, Harvey has a chance to continue his dominance, becoming one of the more underrated free agents signed this winter.

Sean Newcomb

As I previously mentioned when talking about Danny Coulombe, there are noticeably fewer quality left-handed relievers on the free agent market this season. However, after a fantastic year spent between the Boston Red Sox and the Athletics, Sean Newcomb is one of the best lefties on the market this winter.

During the 2025 season, Newcomb pitched to a 2.73 ERA with 91 strikeouts in 92.1 innings pitched. In fact, Newcomb was one of the few relievers in the sport to record at least 90 innings pitched, as one of his greatest traits is his availability.

Newcomb excels at limiting barrels. His barrel rate in 2025 sat slightly below 6%, a number that put him inside the league’s 87th percentile. His four-seamer and slurve lead his arsenal, as both pitches generated opponent xwOBAs in the .200s.

Newcomb is a perfect candidate for any team looking to add a left-handed innings eater to their bullpen for the 2026 campaign.

Jacob Webb

In 2025, the Texas Rangers put together one of the best bullpens in the league. Their bullpen ERA of 3.62 was the fifth-best mark in baseball, which speaks to the dominance of this group. A big piece of their bullpen’s success was right-hander Jacob Webb.

During the 2025 campaign, Webb pitched 66 innings of 3.00 ERA baseball, recording 58 strikeouts in the process. His WHIP finished at 1.03, a number that was fourth among Rangers relievers with at least 20 innings pitched.

Webb was one of the best relievers in the game at limiting hard contact during this stretch. He kept opponents’ average exit velocities under 87 MPH, while posting elite barrel and hard-hit rates. In fact, Webb ranked inside the 85th percentile or better in all three of these categories.

Now entering his age-32 campaign, Webb will be a hot commodity on this offseason’s free agent market.

Taylor Rogers

The 2025 campaign was a whirlwind for Taylor Rogers. He was traded two times near the trade deadline, yet still managed to put up a pretty positive year overall. Now entering his age-35 season, Rogers could be a decent pickup for a team looking for left-handed bullpen depth.

Rogers pitched 50.2 innings while recording a 3.38 ERA and 53 strikeouts along the way. He used his two-pitch mix to get consistent outs on the mound, often being more crafty to make up for his lack of velocity. His sweeper, for example, registered a .204 opponent xwOBA.

Although Rogers’ underlying numbers aren’t stellar, he has a chance to be a valuable innings eater in 2026. He should also be pretty affordable, something that’ll work to his advantage in this market.

Tyler Kinley

After posting back-to-back years with an ERA over 6.00 for the Colorado Rockies, Tyler Kinley had a huge breakout campaign in 2025. There’s a good chance Kinley was a victim of the Coors effect, because as soon as he left the Mile-High City, he was nails for the Atlanta Braves.

Kinley pitched a career high 72.2 innings this season, racking up some of the best marks of his career in the process. He recorded an ERA of 3.96 during this span while also keeping his WHIP below 1.20.

Similar to some of the other names on this list, Kinley was very successful at limiting hard contact this season. He kept opponents to an average exit velocity of 87 MPH, while putting up a hard-hit rate under 30%, a number that placed him in the sport’s 100th percentile.

Kinley will be one of the more interesting arms to watch this offseason, as he has a chance to have a big impact for a contending team in 2026.

Jakob Junis

After losing Emmanuel Clase midseason due to a gambling investigation, the Cleveland Guardians were forced to rely more on other arms in their bullpen to get by. Jakob Junis quickly became one of these arms for Steven Vogt, as he had a huge impact on the team’s season.

Junis was one of five relievers in the Guardians’ bullpen this season to post an ERA under 3.00. He was also one of just three arms to record more than 65 innings pitched in relief, which really shows just how much Vogt trusted him with the ball in key situations.

This was for good reason, too. Junis maintained a barrel rate slightly over 6%, a huge indication of how he handled hitters with relative ease. His changeup was a big piece of this, as opponents hit .167 against the pitch.

Junis is now approaching his 10th big league campaign, and with how he pitched in 2025, he looks like a potentially valuable pickup for a lot of teams this offseason.

Justin Wilson

Coming off of just their second playoff appearance in the last five years, the Boston Red Sox relied heavily on their bullpen to keep them close in games. They had the second-best bullpen ERA in baseball, and lefty Justin Wilson was one of the more underrated members of this group.

Wilson appeared in 61 games during the 2025 campaign, regularly providing the team with valuable innings in relief. He registered an ERA of 3.35, struck out 57 batters, and handled left-handed hitters with relative ease.

Among Red Sox relievers, Wilson was one of the better pitchers at inducing whiffs. His whiff rate of 31.9% was in the league’s 91st percentile, which is a huge reason he was able to rack up so many strikeouts this year as well.

Now on the free agent market, Wilson is an underrated reliever worth keeping an eye on. He could easily become a key bullpen piece for many teams looking for an upgrade.